Every time I attend a concert, I'm reminded of just how little people know about how cameras work. That in itself is really not a problem for anyone except the people taking crappy pictures, but then we must consider the flash.
I propose that we require that people demonstrate at least a minimal understanding about how the bloody flash works before they're allowed to carry a camera. How stupid do you have to be to think that the dinky flash on your cheap point-and-shoot is going to effectively illuminate the band 300 feet away from you? Does it not occur to you that thousands of dollars worth of incredibly bright spot lights might provide enough light for your snapshot without temporarily blinding everyone within 20 feet of your useless piddly micro-strobe? Or did you really want to get a nice exposure of the backs of the heads of people 1 and 2 rows ahead of you instead of taking a picture of the act you paid Ticketmaster $50 to see?
I guess if you're clueless enough that you can't figure out how to turn off your damned flash, you aren't smart enough to google "inverse square law" or understand the content of the search results.