YAnbu in that you can ban anything you want.
What gets to me is it's one thing to know the game and as a result allow your children to play it or not as the case may be.
The problem comes when parents have no idea about the games their kids are playing and a couple of months down the line are up in arms (when they finally bother to look at it) and want the game banned.
This is going to destroy the games industry for adult players eventually.
Australia already will not allow 18 rated computer games.
Adult gamers will find stuff aimed at them banned because people can't be bothered to look at/play/have any knowledge of games before they buy them for their children.
Ultimately it is up to the parent what games their children play, not the industry, but because of those that don't check up on it, the industry will end up being censored because they can't be bothered to actually to check out what their kids are up to and also in the style of one daily mail writer (this was a while back) - they apparently have no power to stop their kids playing games they don't like in their own home
I have no issue with parents who know the game or don't have an issue with their child playing 18 rated games when they know what they are letting themselves in for. I may not agree with it, but it's not my desicion to make.
It's the ones who get up in arms to ban the games BECAUSE of their failures as a parent I get with. Why should mine or my dp's gaming be censored because of them? I check what games my child plays, I know what I will allow and what I won't - same as films/music/books or anything else.