The effects of wealth on outcomes meaningful to most humans look mostly like a step functions, with some continuous-lookin' bits here and there. Anecdotally my assumption is that partying x wealth is bimodal, with peaks near the top and the middle-bottom of the wealth distributions. But homeless people and people scraping by on two minimum-wage jobs, both of which comprise a larger portion of america than when I was a child, are unlikely to be able to host or even often attend parties, like I think there's a sharp step to basically zero after a certain poverty line unless you're in a really integrated community (also less common over that time period, to be fair)