The main problem with the law is that it address the sale of "M" rated games to children.
But the whole idea is to keep these titles away from children.
Sense this is the idea you would have to have the law prevent the sale of "M" rated titles to anyone who may purchase them for a child as well.
Anyone who has worked retail knows parents are the ones who purchase "M" titles for kids.
Unless California is going to start a prosecuting parents and charging them with child abuse for getting there child a "M" title game they should just drop this law.
Governments need to let adults make there own decisions for themselves and there children.