You don't hear "bourgeois" used as a swear word very much anymore, yet "nouveau riche" still serves the purpose well. If this were coming from old money people, it would be understandable, but it's mostly coming from the nouveau riche themselves. That's typical of the culture's obsession with making the enviable self-flagellate in public (another example is "White guilt," a disease that only successful Whites suffer from), but in this case there does seem to be a deeper hatred.
What usually makes a person newly rich is that improving environmental conditions produce more smart people, and that the economy begins to offer more opportunities for smart hard-working people to make good use of these traits. You'd think that, since we so treasure the rags-to-riches ideal, we'd be more comfortable with the nouveau riche, as questionable as its tastes may at times be. Instead, we focus so much on how gaudy are the women's purses or the men's cars -- sins which are really more venial than cardinal -- that we overlook the wonderful fact that the smart and hard-working do not have to squander their talents picking potatoes anymore.