Not necessarily because of the band members, but yeah, you want to cover up the noise of people chattering away in the back. Music can also sound better when i

Not necessarily because of the band members, but yeah, you want to cover up the noise of people chattering away in the back. Music can also sound better when it's louder, up to a certain point - if you're recording and mixing a piece of music, you want to do so at a very moderate volume, because if you crank it up loud some of the imbalances in the mix become less obvious. That said, there's 'loud enough that the music sounds good and you're mostly hearing music and not audience', and then there was the Prodigy concert I went to, where I was wearing earplugs and my ears still hurt. Amazing concert, but holy crap, probably the loudest situation I've ever encountered. I've also been right in front of the speakers at a festival dance tent, and my earplugs rattled due to sound pressure, which was unnerving but quite funny.