One factor is easier to change than the other. The car owner can change cars or repaint it. A black man can't trivially change skin color, and they're going to

One factor is easier to change than the other. The car owner can change cars or repaint it. A black man can't trivially change skin color, and they're going to feel that making an effort to be productive is less worth the effort. If a significant number of additional stops which they have no control over would impact their job performance and reputation (frequently being late, etc), risking getting them fired at no fault of their own, what are they going to do?