Why the people are trying get more and more money even though they have money

People do not have contentment, sad to say it's in our nature. Once people earned something he wanted, then he'll desire some more. And it also breaks my heart whenever rich people discriminate the poor(hardworking ones), why not just help those deserving poor people to have a permanent and compensating job instead of maltreating them. (From a different side, not all poor people should be helped for they, themselves do not help themselves, SOME)