All primates groom themselves to have straight, clean looking, glossy hair. Humans are not going to voluntarily wear clothing that shouts “I’m one of poor or autistic.” People who are much, much poorer than the average OECD inhabitant care greatly about their appearance.
Yes, but lots of primate species also conduct a lot of rape and bullying. The best distinction I have between humans and other primates is that humans can change what they have believed to was their nature. Until somewhat recently, on this planet, all primates lived in a jungle.