I wouldn't say it is regional pilot specific because I have seen regional and major pilot that look less than professional in their uniforms. I think it makes a difference to some pax. I know if I was a pax that was fearful of flying I would feel much better if the pilot walking to the plane was wearing his uniform in a professional manner and not looking like a slob. I think the truth of the matter is that how someone chooses to wear their uniform is a matter of self respect.