From my limited knowledge and viewpoint, there is a generational divide, a regional divide, and a class divide. When everything is averaged though, the household income is still the strongest indicator of how many cars you own, and most national statistics prove it.
True, class divide is a real factor: The upper class doesn't own cats (aside from "fun" cars for collecting) but leases them.
Somewhat more serious: Especially here in Germany there is a strong incentive to give cars as a job benefit instead of a pay rises as there is less social insurance to be paid. Thus there is a strong motivation for anybody in a well paying job to get a car. This directly leads to that class divide.
