I know this is an almost rude question, but I've been wondering for a while. On forums and whatnot I sometimes see users with systems that must cost tens of thousands. Sometimes it looks like at least $50k.

Do such users tend to be particularly wealthy, or just spend a particularly large amount of their income on hifi? A little of both?

It's not polite to enquire about people's incomes, nor question the value of their purchases; but if I don't ask, I'll never know.