Suburbia is the mode of urban development that is most heavily subsidized.
There would be MANY more people opting for dense (or even not-so-dense) urban living, as rational actors in a market-driven system, if the true cost of development was reflected in the price of tract housing properties.
Having a fully-serviced plot of land with enough room for dirt yard, gravel driveway, and a great snout of a two-car garage poking out into a cul-de-sac is a luxury, not a god given right, and it's about time that it should be treated as such.