When I go, I usually just buy the kinds of things I can't make... small paintings, soaps, and now I'm on the lookout for a yard spinner!
I don't mind people looking closely at my items, but I draw the line when they try to take pictures with their phones. That's the height of rudeness, and I won't hesitate to tell them so.
I haven't sold at a craft show in several years. I got tired of all the work setting up, only to have 99.9% gawkers and so few sales. As a buyer, I get tired of seeing the same old, same old everywhere. Painted wooden signs, decorated wooden crosses and the almighty fleur-de-lis! I don't see crosses as something to make pretty and decorate your home with. That's missing the point. And the fleur de lis must be the decorating staple of the South. Likewise, I miss all the jewelry sellers. I rarely wear it, so it's easy to pass by those stalls, tho they seem to do pretty well.
Guess I'm a craft show curmudgeon.