It was truly disturbing to see so much ignorance about what goes on behind the scenes in preparation for a wedding, to see how sunk we are in consumer mentality rather than collaborative mission, and to see how little the time and service of the priesthood was valued. Even those in clerical office whom I expected to know better weighed in on the wrong side, which means that their parish/episcopal staff have been shielding them effectively from the nitty gritty of wedding preparation, especially the financial bits.
Here is a brilliant article which I had high hopes of exonerating me from writing about this topic: https://canonlawmadeeasy.com/2013/11/07/stipends-and-sacraments/
It includes all the canon law references that pertain to stipends for Mass offerings and sacramental celebrations. Please read it.
Let's go back to the plan of God in the scriptures.
We see Melchizedek provide Abraham spiritual services of a ritual nature, and Abraham in thanksgiving to God for the battle victory and for all else God had done for him including the post battle blessing, gave to God through Melchizedek a tenth (tithe) of everything.
We see in the offerings and sacrifices made according to the law of Moses, that specific portions of it were to be set aside for either the consecrated priesthood, or for them and their families. It was the way God designed for the priests and their families to be able to give themselves fully to the requirements of the ritual worship of Israel.
If you want to delve deeper into the meanings of Temple worship, this article by a Presbyterian scholar is helpful. https://www.fpcjackson.org/resource-library/sermons/priestly-pay-the-priest-s-portion-of-the-grain-offering
And this article on the tithes of the Old Testament is useful also, https://www.ministrymagazine.org/archive/1958/09/the-three-tithes-of-the-old-testament
Now I need you to comprehend how this tithe and offering process and the spiritual impetus behind it is very different to the crime of simony we see in Acts 8, where Simon the magician notes that people that Peter and John impose hands upon receive the charisms of the Holy Spirit. He wants to be able to do what Peter and John do, and offers them money. Simon would be set for life being able to charge for passing on these valuable charisms to others. Peter gives him a vehement rebuke.
The Church still takes this seriously, eg if an object has been blessed it can no longer be sold.
The closest thing I see to simony today is people doing 'prophetic activations' online, and charging money to be part of them. The promise is that your capacity to receive prophecy, dreams and visions etc will be unlocked through prayer. That is very different to attending a paid conference or seminar that has times of prayer ministry where such things might happen but are never guaranteed to happen, and would only happen if it was God initiated.
'What you have received without charge, give without charge' has to be balanced with 'the labourer is worthy of his hire'.
The tithes and offerings are made first and foremost to God, and then generally the tithes keep the families of priests and the temple and its furnishings and other requirements for worship (vestments, musical instruments, offering vessels) in good repair, and part of the offerings goes directly to the priests.
From this thinking comes our first collection for the upkeep of the priests and our second collection for the upkeep of the parish, and by extension the diocesan services. It isn't paying for sacraments as much as keeping the mechanisms going that make receiving the sacraments possible.
I really hope you get that distinction, because that is what underpins the thinking on marriage fees.
In a perfect world couples getting married would naturally express their thanksgiving to God for such a priceless gift. That expression could be through money, or in offerings in kind (cattle, produce), manual labour as often happens in rural impoverished areas, and given to God through both parish and priest, and also to the poor and needy. But it falls under the keeping the mechanisms that make receiving the sacraments possible thinking, not under the payment for sacraments thinking (which would be simony).
So let's look now at what goes on behind the scenes in a parish to make a wedding possible:
There is paperwork to be done to apply for the marriage certificate for the civil side of the marriage dealing with government laws and regulations. Then there is the paperwork to determine whether the bride and groom are sacramentally capable of contracting a Catholic marriage. That's why you need baptism certificates, confirmation certificates. They usually have to be verified by the parishes in which those sacraments were received. Rarely is this simple, usually it entails significant time for parish secretaries to complete. If there have been prior marriages it is even more complicated. If the paperwork cannot be verified, then the spouse to be without the verification is invited to have a conditional baptism and chrismation (Dear God we don’t know whether this person was validly baptised or not, but You do, if they weren't baptised back then open up the gift of Holy Baptism for them now, and if they were validly baptised back then, please bless them for recommitting themselves to You).
The priest is obliged to do all he can to ascertain whether both bride and groom are both able and capable of giving full consent to the marriage. Often this is done through a series of marriage preparation meetings and talks, and depending on diocesan policy attending some kind of marriage preparation course eg Engaged Encounter. Frequently this process time with the priest is the only time a couple gets to focus on preparing for the marriage, and not just the wedding, and the insights and advice are useful for a lifetime. Everything else (invitations, wedding cake, formal gear, photographer etc) is focussed on the wedding day, only this is attempting to set you up to succeed in married life.
Then there is the work to be done selecting scripture readings and hymns and which of the various options for prayers during the Mass or Liturgy of the Word are preferred.
The priest has to prepare a homily. Ditto if a deacon is presiding over the ceremony. Preparing homilies takes time and effort.
Then there is the time the priest gives to the wedding ceremony itself, getting there early, often doing part of the set-up.
These are not inconsequential commitments of time by both priest/deacon and parish staff, and it doesn't stop there.
Those doing the music have to be contacted and scheduled, they have to practice the music. They also have to submit the copyright permissions for the music chosen, and there are fees to use music depending on what kind of copyright payment mechanisms the parish already has. Popular hymns would already be paid for under parish licence, less common hymns may attract additional charges. If the musicians don’t already have the music desired, they have to pay for the sheet music. Copyright is charged whether the music if live or pre-recorded, because no matter the delivery method it is still being utilised in a public setting.
In high summer or deep winter the bills for lighting and air-conditioning will be higher, but even outside of those intense climate times there will still be light and power usage.
Altar servers may be required, and they give of their time too.
If there is a wedding practice beforehand, then that is additional time given by priest, musicians and others.
The parish also has to cover itself in case things go wrong, and that happens more frequently than you imagine. Normal things like a child spilling a drink, or throwing up, or lots of grassy detritus leftover from weddings of people from Pacific Island heritage. Someone has to clean them up, and sometimes the damage is costly to repair.
Then the other things that can go wrong include a wedding guest having a fall, breaking a bone or two, or similar calamity, and then suing the parish. Public liability insurance is no longer cheap, and the more times unfortunate things happen the dearer it gets.
For particularly eye catching chapels and churches the waiting lists tend to be longer, and in the meantime the couple can split up (and not tell the parish, it happens more than you think) or find another venue they want more (and not tell the parish, it happens more than you think), so these were the first places to ask for some kind of deposit to reserve a place on the parish's marriage calendar. If you have paid for something, you are more likely to show up, and more likely to contact a place to get your money back.
For cathedrals there might be extra costs due to forgone revenue from tourist donations when the wedding is taking place and non-guests are dissuaded from entering.
Those eye-catching chapels and churches usually have a high annual maintenance bill, and some of the 'fee for use' will go towards that bill.
Often parishes help with putting together a wedding booklet, and that alone is a time consuming task taking many hours even if working from a basic template, and even if there are no alterations and changes of mind about readings and hymns etc along the way. Add printing costs to that.
It definitely isn't free for a parish to provide the wherewithal for a marriage to take place. Expecting all of those services to be provided gratis even for a super active member of the parish is unreasonable.
Generally there is a flat fee that encompasses all these things, and in reality it is a token only and not the full cost at all. The suggested voluntary and yet expected stipend for the priest technically should be separate, but parish secretaries are pragmatic and they know that bundling things into a single fee reduces the amount of time they have to spend explaining why a fee is necessary in the first place. Explaining one is hard enough, explaining two, forget it! Let alone all of the histrionics and other verbal abuse that exudes from people stressed out over wedding preparations that such fees illicit and the parish secretaries cop.
With weddings of two practicing Catholics running at around 1 in 10, or less, you have to factor additional time educating brides and grooms with minimum understanding of Catholic ritual.
Because the knowledge of how things are done has rapidly decreased with each virtually unchurched generation, parishes were finding that the priest's stipends were not even on the radar. Even the best of us gets upset after receiving no tangible appreciation for time and effort five or more weddings in a row. In former days (many decades past) providing a stipend was just general knowledge and expected behaviour. People back then knew what amount was a reasonable offering, they don’t now. And it is not just weddings. Parishes have had to introduce the fee structure for funerals as well to ensure that the priest gets a minimum token of appreciation/stipend.
Cases of genuine hardship will always be accommodated somehow, if requested respectfully.
So what is reasonable fee wise? A lot of people are going to be putting in a lot of hours from the parish making your wedding day possible. May I suggest that you take the average hourly wage/salary of bride and groom and multiply it by 10. Even though 10 hours is an extremely conservative estimate, the vast majority of fees will be under that. Be grateful, and cheerfully give. If over, then the parish you are dealing with has high maintenance and security costs and/or a recent spate of very expensive bad experiences.
Some people have suggested taking up a once a year collection to subsidise the fees for weddings and baptisms. I suspect you will find that the user pays principle has been so embedded in Western civilisation that the average parishioner will be outraged, because the people most likely to be subsidised are obviously absent from weekly Sunday worship. It would also take away that biblical notion of expressing personal gratitude to God.
If you still think that fees for church weddings are utterly wrong, then go and consult an expert. Contact a parish secretary, bring her (or him) a cup of coffee, ask them about why that parish has wedding fees and be prepared to listen and listen and listen as they tell you the stories behind each and everyone one of the fee decisions the parish has reluctantly had to make.