Worked hard, won a lottery, whatever. It mostly says that these are people with tens of thousands to burn on fun stuff, and such people are a rather narrow slice of the population. There's nothing bad about that, it's just a rather niche community, whose opinions may not be very relevant for the large majority of people outside that niche.
HN is that niche community though. HN is a forum targeting a niche community that skews technical no matter where someone is physically from, and that community skews relatively rich. Concern trolling that there are starving kids in Africa when there are literal billionaires posting here; I mean sure, I'm not saying we shouldn't say something for fear of their feelings. Nor am I saying that everyone here must be rich in order to comment her. Just that some members of the niche community can recognize are inordinately rich. Advertising eg the Volonaut here will likely generate a couple of sales, and if you thought a $3k laptop was a lot, definitely don't look that one up.
HN is a specific slice, but not along the financial line. For each @pmarca or @pg or other founder who has made many millions, there is likely 10k other users, mostly engineers, but not only, all the way to people who are currently unemployed and homeless. The fact that HN has "everyone", and a uniquely relevant person would almost always show up in every thread, is one of the very attracting properties of HN for me.