Lol, I doubt race is really still alive in the DBverse. They have animal people and aliens living among them so it would be pretty stupid to pay attention to small differences in normal looking humans which is probably why Saiyans never had issues blending in save for the tail. I believe the clothing thing goes by region too since you really can't tell anything racial wise by just looking the characters. As for Goku, he is Goku. Period point blank.