We're providing therapy for them. Poor motorists, trapped in their cars, feeling like insignificant specks in the vast machinery of modern life, see a free soul on a bike and identify it as someone even more insignificant than they are. They see someone out in the open, unprotected in any way, on whom they can vent their frustration, brought to a boil by the constant annoyances that come with driving anyway.
We're providing a service. We just have to figure out how to bill for it.