For whatever reason people have a very different relationship with travelling in their own car and via some other form of transport. The perceived cost of a trip seems to drop for a lot of people, both with regards to price and time. Perhaps less so in the millennial generation but in the preceeding generation there is a very strong association between owning a car and personal freedom.
Probably because owning a car means you can go anywhere your wallet ($ for gas) and time will allow you to go. Anywhere, any time, with very little hassle. Taxis come close to this, but only in and for (geographically) small areas/trips. Bicycles also come close. Other forms of transit are limited in terms of endpoints (*ports for planes/ferries, stations for trains/subways, stops for buses), time (dependent on the schedule), and may cost more.
Owning a car often gives you a lot of options you don't have without it.
