<I>step 3) optionally, in the case of a kid getting someone who is not their parent to buy the game for them, get a signature and a phone number or something..</I>
This isn't alcohol, or cigarettes... Does anyone really worry about some 8 year old playing a video game and when his parents tell him he has to go to bed he gets mad and grabs a gun and wants to keep playing?
Parents have to enforce the rules! Not retailers, not cops, PARENTS. If you have a kid and you tell him/her he can't play that game, GUESS WHAT, you'll have to watch him like a hawk, check his computer/xbox multiple times per day, sneak around his/her room while at school, eaves drop on him with his friends, meet his friends parents, find out if his friends have the game, monitor what he spends his money on, and that is just for starters! KIDS ARE SNEAKY LITTLE BASTARDS. I was!