If this is the case, then how do people with no reputation then gain reputation? The reason I have my reputation is because people traded with me and I followed through with my word, though if they followed your logic I wouldn't have any of it as no one would have traded with me.
Escrow is a way to trade with people with no reputation and be sure that you won't be scammed. Though apparently using escrow is a bad move because you should trust the people that you trade with.