I'm sometimes playing on stage, and also visiting concerts, and one of the biggest nuisances nowadays are people with mirror cameras looking like shotguns - and flashing, clicking and buzzing all the time.
However, there are cameras today which are good enough to go without flash, and without mirror and sound -- For example, my beloved Fuji X100.
If you are on stage, it is a shock to get a flash right into your face. And if you concentrate on playing a more subtile part, then it is a nuisance to hear the clicking or even buzzing, you feel like the audience is not listening.
So: Why do so many photographers in 2015 still use flash and noisy cameras in concerts?