Violent video games and kids

I’m rather confused. I was just reading an article on MSNnbc’s website that the California’s courts have struck down a law that was designed to prevent the sale or rental of violent video games to minors. The reason I’m confused is that I thought that there was already a rating system in place that told stores/vendors to NOT sell video games that are rated for “Mature” audiences. Anyway, the courts ruled that it was up to the parents to keep their kids from playing violent games, not up to the stores. This does not make a lot of sense to me. If kids are not allowed to go to “X” rated movies, then they should not be allowed to buy or rent “Mature” rated video games! Although I agree that parents need to guide their children, the sad fact is that many times children will “sneak behind the parent’s back” to get things that they really want. I think that a law preventing minors from buying or renting “Mature” games is very appropriate!