What if a company makes a large number of cars? Would they make cars that minimize travel time for their occupants, or for all people who buy cars from that company? Would multiple companies band together, and make cars that minimize travel time for everyone who buys cars from any of those companies?
They'd all band together and create a regulatory agency which ensures everyone's doing that. This is what happens in other industries, and this is what happens in car manufacturing.
When a collision is unavoidable, should a self-driving car try to maximize the survival chances of its occupants, or of all people involved?
http://www.wired.com/2014/05/the-robot-car-of-tomorrow-might-just-be-programmed-to-hit-you/