That makes me think of another problem with car culture, that's kind of the mirror image of the phenomenon you're describing...

Like you said, a lot of people just forget driving is dangerous. But for people who haven't forgotten, we just get used to living at a certain level of life-or-death stress, for possibly hours a day, when we're in our cars. I don't think it's very conducive to overall happiness.

Don't get me wrong, driving is a really easy game, and it's fun to play sometimes, but the consequences of slipping up and losing can be pretty rough.