It's no longer socially acceptable to let your kids walk to school, or walk to the store to get stuff for you, or do anything without adult supervision. And since adult supervision isn't possible 100% of the time, the kids get plugged into video games and the TV, where they are unlikely to get 'hurt'.

Maybe that changes when the kids become late teenagers, I'm not at that point yet. So now that the adult has to do the shopping. But again you can't leave the kids at home alone and go shopping, so you have to take the kids with you. Well, there goes the possibility of biking or walking, so you take the car.