Much of mass transit (airplanes, tour buses, Greyhound, ocean cruise lines, etc.) are profitable.<p>There are things that people are not willing to pay for, and government types have labelled these things "market failures", which, BTW, is a misuse of the term.<p>Government has then stepped in and run programs that people are not willing to pay for.<p>So the question really boils down to "how would you make something that noone has ever figured out how to make profitable...profitable?"<p>It's a bit like recycling: there have been metal recyclers for centuries.  People do not recycle glass and paper because it is a value DESTROYING activity.... and thus government got involved, and requires people to separate their trash streams...before recombining about 75% of the "recycled" materials and putting them in landfills.<p>The only good answer to this question is "mu".