True, but those people who moved out found that the externalities of their driving made driving itself less pleasant. It's great to live in the suburbs and drive in to the city when you're the only one doing it. When parking gets scarce or the roads are too narrow or congestion is bad, though, it gets annoying. For the US, the response was to mandate large amounts of parking and large roads that are built so they can move a certain number of cars a certain distance per hour. However, little thought was given to the fact that by doing so, you end up making the distances larger, because everything's farther apart, because it's surrounded by parking (among other reasons), wider streets, larger interchanges, etc.

Those things that make driving more pleasant also make walking less pleasant (walking next to Wilshire blvd in LA isn't exactly pleasant, for instance), so more people drive, so more people demand auto-oriented infrastructure, and so on.