Agreed, the industry and game retailers already do this, it is not law but an agreement. I actually have little problem with this if we just use the current rating system and make it legal. The problem is this will be reported as a scare piece, and just add fuel to the fire that a 8 year old can go in and buy a mature rated game. They cannot. The other thing that irks me is all the teens playing mature rated games. Dear parents this one is up to you to enforce, if you want to to use electronics as a digital nanny make sure your nanny is teaching them things that you approve of.
The internet has way way worse things on it... Hey Parents that are complaining, are you watching your kids internet usage???