you know its not the venue, its the promoters/artists that decide the policy, a lot of artists don't mind if they aren't professional lenses, and if the flash is turned off. I would never do a flash in Bono's face, just get fast film, like 800, even 400 is ok, and if it's digital you have to do the settings, which are complicated, otherwise without flash they are blurry. People have always taken photos at U2's shows as far as I remember.