It's not just the photographers. It's anyone who pursues their own disruptive thing during a performance. Like singing along. I saw Jethro Tull a couple of years ago and had to get quite nasty (after a couple of polite requests) with the guy behind us who was singing along with Ian Anderson very loudly. If the performer doesn't invite you to sing along, please don't!

And then there's the coffeehouse gigs where a table front and center is full of people with no interest in the music. It's really hard to connect with an audience when you have to do it past a group of people talking loudly. I don't think there should be any requirement that they pay attention to the music, but why don't they move to the back? Why doesn't the management ask them to? It makes me feel like I'm a TV babbling away in the corner.