You all are going to think I'm horrible...but I'm going to risk it anyway.
A couple of years ago my cousin and her husband celebrated their 25th anniversary with a big party and they had the disposable cameras on the tables. Some other cousins and I decided to have a little fun with the cameras and went around taking pictures of people just as they were opening their mouths to take a bite of food. It was really funny!!

My cousin told us later she wondered why there were all these pictures of people eating. She appreciated the humor (thank God) and still enjoyed the pictures.
Because of that, I agree with the other brides that you should expect that these pictures are meant to be "fun" and not to give you good shots of things at your reception. In fact, I would make it a "game" for your guests. Give them a list of things to take pictures of...like "oldest couple dancing" or "baby and parent dancing" or "everyone at the table next to you" or something like that. You can even decide to do some funny stuff (a la people eating) so that you can have some fun too!

I'm off to hide now...