I'm not convinced money or religion or any other "tangible" factor you can point to is the cause of the problems with humanity...I think it's human nature itself. If you take away one excuse for conflict, we're great at finding a new one. I am convinced discrimination still takes place on Earth--but most importantly, rather than seeing our "us and them" as a matter of internal race/religion/ideology, etc., humanity and the Federation still DOES have an "us and them" mentality but towards the other species
out there. They pushed it outward but did not get rid of the problem. Thinking that they did will only get them in trouble.