It is usually on the contract but usually during the formal sessions. You cant expect anyone not to bring cameras during the ceremony or receptions.
We recently had an issue where the aunt of the bride brought her studio in a bag, and proceeded to whip out her D3 and 2.8 glass. She had been asked to photograph the wedding but declined. She thought she'd get away with it, but failed to realize she didn't know me so well. I can tolerate a few uncle Tom's with digital whatevers, but when you are a self admitted, studio owning pro coming into my hired territory... show some respect.
This grey area confuses me. At what point does a camera become unacceptable? I know it's ultimately up to the pro shooting the event and of coarse the bride and groom but is there a general rule of thumb here? I know I would be more likely to get the pro's blessing with my little Kodak than I would with the D7000, a fast prime and an SB900. What would be the middle ground here that would allow me to take the best snapshots without ruffling any feathers?
I would say that most of the weddings I have done, there is always at least one guest with the latest and greatest gear. Some of it is gear I would like to own. I would also say that at over half the weddings I have done, I have had at least one guest ask me what settings I was using, or why their shots weren't coming out how they wanted. You know what I do? I tell them. If they don't know how to set their camera, I set it up for them. Then I smile, and give them a card.
We always have guests coming up to us after the wedding telling us how great we were, how professional we were, asking us where they can view or buy the photos, and telling us how different we were than other photographers they have seen. I have just been assisting weddings with Visions in White for about a year now, but I've already seen bridesmaids who were the brides at previous weddings, and brides who were bridesmaids at previous weddings.
If another pro wants to institute a 'no camera better than mine' policy, or even a 'no cameras at all' policy that is fine by me. I like to help guests get shots they can be proud of. And when it's time for them to hire a photographer, they tend to hire a photographer that they know will be courteous and helpful to their guests, and not treat their friends like they are competition.
I think sometimes photographers get so caught up with looking through the lens that they forget that people are watching what they are doing as well. The thing about shooting a wedding is, most of the bride and grooms friends are around the same age and a good majority of them will be having a wedding in the next few years or know people who are. It's just poor business sense to be rude to those guests or their friends.
Just my .02.