Used or Pre-Owned?

I just heard an ad on the radio for a local car dealer. It occurred to me that used cars are now commonly referred to as "pre-owned" cars. But the prefix "pre-" doesn't mean "previously" does it? It means "before" as in pregame, Precambrian, prepaid and, well, prefix. A pre-owned car should mean a car that has not yet been owned--and therefore new. Right?