That very well could be part of it. I also think there is some bit of class-ism. If I look the part, I look like I have other optins ancd could be riding around in a car if I want so they are a bit more considerate around me. If I look like a long-haired hippie drunk with no drivers license on an old mountain bike or someone who can't afford a car, if they run me over, it is no big loss for society.