My parents kind of cared until I was sixteen or so. I think they had a lot of misconceptions about games like GTA, and once they actually saw them played, they didn't mind as much. Once I got older, they didn't really have a right to stop me doing anything, anyway.
Video games are just scapegoats. Blaming something on a TV show or movie would be just as stupid, but nobody even does that, because they're accepted as a valuable part of culture. Anyone who's going to, for example, shoot someone at random was screwed up by a long list of genetic and environmental factors, of which video games, movies, TV, books and music are an extremely small one, if one at all.
Then there's the fact that consensual sex between two adults is more objectionable to America as a whole than (literally) blowing off someone's head with shotgun, and I have no interest in the debate.