Except that when you take into account the externalities, mass transit pays for itself, while suburbs don't. So mass transit should be partially publicly-funde

Except that when you take into account the externalities, mass transit pays for itself, while suburbs don't. So mass transit should be partially publicly-funded. Suburbs should not. Mass transit reduces congestion, reduces land usage, reduces environmental damage, reduces poverty, reduces pollution, increases quality of life and is usable by the vast majority of the population. Suburbia infrastructure only serves those living in suburbs and has the opposite effect of each metric listed above.