We live in a flat in South London and could never, ever afford a house (short of winning the lottery). DC goes to private school and while the vast majority of parents are very nice there are some who make it clear they aren't bothered talking to me and id stretch to say that one clearly doesn't like me. I don't think I'm imagining it's happening and that it's happening because we are less well off.
Would you look down on someone who lives in a flat? Would you be happy to go around to their home? (when we can obviously!)