Certainly not! The Grand Theft Auto games have always been over the top parodies of action movies, which themselves are pretty over the top when compared with reality most of the time. I'm firmly in the "ethically neutral" camp, philosophically speaking, when it comes to the issue of in-game content. There's no such thing as an immoral action in-game because those actions are not being committed against sentient beings. There is more violence inherent to kicking your easy chair than there is to blowing away a guy on the street in a GTA game.
I certainly think children could be socially influenced by the things they see. But these games aren't for them and it's incumbent upon parents to curate their child's environment appropriately. Society does not owe them censorship, rather self-censorship is the appropriate course of action here if your young one isn't yet mature enough to understand that actions in-game are not the same as actions in real life. I would liken it to letting them watch Wrestling. All the little boys loved Hulk Hogan and the Ultimate Warrior when I was a kid. And all of our parents were quick to explain to us that Wrestling is just an act. They're not really harming each other, but performing a sort of gymnastic magic show. To behave that way in real life would injure, or kill someone.
For the same reason I've never gone out and "Tombstone"ed someone, I'll never rip a guy out the of the car, pop him until his life meter is gone, steal his money, and drive off to commit vehicular felonies. Media can never objectively be "too" anything. It's always a subjective matter and thus it's a personal responsibility that we each must decide for ourselves where our lines are, and to be adult enough not to cross them while allowing each other the same right to make their own choices about where that line is.
