You have a strong point in regards to the photo taking. I hope I'm one of the considerate photographers. I wait my turn and often have pictures of peoples backs. I know there are some rude people out there but for every rude one I'm sure there are two polite ones. I have become very fast at taking my photos and very sneaky at times too!
One reason I find photo taking advantageous is that I can not stand or walk for long periods of time so once through the show is about all I get to do. By taking photos I am able to go home and enjoy the quilts again and appreciate all the wonderful stitching.
If they are selling photo CDs that's wonderful but I've seen that at only one show I've attended.
That's my case for photo taking.