buses, trucks, emergency vehicles, bicycles on the roads, taxis, people going places too out of the way for public transportation to service and whatever other

buses, trucks, emergency vehicles, bicycles on the roads, taxis, people going places too out of the way for public transportation to service and whatever other uses of the roads that aren't immediately obvious would all still benefit from this. smoother traffic flow and reduced time on the roads would also reduce accidents, which would require fewer vehicles be manufactured, which is a nontrivial environmental impact in and of itself. oh and fewer humans would die in horrific accidents.