It's definitely the reserve of the educated and intellectual. Its their grime.
I haven't been to such shows for ages and probably will never again, but when I went to noise shows it was all very square arty/student types.I'm not up to speed enough on scenes and structures to know how much of a general thing this is, but I always find it weird that when we go out to see some sort of ear-splitting racket, it's always either sex / power / death / magick weirdos - maybe in their slightly more dignified old age now - or "cool dad" types in jumpers and converse, with very little in between. Maybe some sort of convergence of weirdo industrial and experimental psych? Not sure.