I got married in a Catholic Cathedral. I paid for the privilege. The grounds were lovely and made for great photos. I'd find it irritating if someone decided, especially during the time I had booked, to use that same backdrop without paying.
Here you have to pay for a permit to have your wedding photos taken at local parks, in a nearby city, you even have to pay to use a popular downtown street area. I had my photos taken at the local university. The permit charge is $100 for students and $250 for non-students and it gies you free reign of the entire campus though you are expected to be considerate of any other wedding parties that also have permits. But, it would be very unfair for a couple who paid to have to share with those that didn't. And even if there are no other couples there that day, you're taking advantage by using a venue for free that other people pay for