Yes. I do take photos of all the quilts. It's one of the reasons I go to all four days.
Why? To enjoy the ones I love over and over again. And to analyze the ones I don't like: colour combination is at the top of the "Don't like this"list.
Every show I've been to has allowed photography.
The exception was a special exhibition of a particular artist who apparently didn't want her designs photographed. Fine with me but I wish I could have told her that if I'd gone home with photos of her quilts, I would have bought several of the designs later when I had the $. (BTW, they were too complicated to copy from a photo.)