So this raises an interesting question. Does Amplification create the talking and the lack of manners by the audience?
I think the answer is, yes, it does - but not amplification of the particular performer at the moment, but a whole generation - well, two generations by now - growing up listening to amplified music. Often really loud amplified music. They take it as a given that the music will be so loud that you can talk loudly while it's going on, and people around you can still hear it.
Plus, of course, many young people now are even deafer than us old f*rts, from listening to loud amplified stuff for so long.