Well, we don't buy brand new cars anymore, so my car was dinged when we bought it. I don't worry so much about the cosmetic stuff, but I do want a car that runs (after all, that is it's sole purpose). I also don't want the inside of my car to be disgusting since that's where I actually have to spend a lot of my time (with two kids to drive around), so I always bring in anything that doesn't belong in there whenever we get home (trash, toys, kids' school papers, etc.) so that it doesn't pile up and become a landfill. My husband's car, on the other hand, is an absolute PIT! I HATE riding in his car because it's completely disgusting all of the time. It really annoys me. He spills things on the seats and doesn't clean it up, so the upholstry is destroyed. The carpets are no better. When I handed over the keys to our SUV to him (when we bought a minivan for me), that car was in great shape, even with two kids riding in it all of the time....now, not so much. He had done this to our last car too (which we sold when we bought the minivan). He knows it bothers me, but the man is just a slob in his car! I would be REALLY mad if he destroyed a brand new car, so I guess I'm glad we buy used. ;-)
Anyway, I suppose your theory holds in our household. I tend to get the car maintained on a much more timely schedule than my husband. I think it's because he doesn't have much time for oil changes and stuff with his job (he hardly even gets lunch most days), so sometimes we switch cars for the day and I'll do the maintenance for him, but it's usually when he tells me that the car is likely to blow up if the oil isn't changed soon. Ugh! Men! LOL!