blood in HP is a magic version of the class system, thought muddled to be sure. Arthur and Molly are pureblooded and so are at least upper middle class (honestly the implication is that Molly married down a little bit iirc), so being poor is more about not caring about class and having a lot of ~love~ than a true character defect. It obviously bothers Ron and Percy and it always annoyed me that they wouldn't accept Harry's money, but pride is supposed to be like honor here, i.e. the mark of nobility. You're not supposed to care about money and if you have it, you're supposed to be like Harry and try to give it away as much as possible but never care for yourself lmao.