This topic hits home with me too. I'm am an unabashed gamer, and have been since Nintendo, that's right bitches. 8-bit 4 life.
Games have evolved since then, and naturally so has the content. There are games out there, that I would never want my kids to play, and I'd have to take a good long thunk on others before I let my teen play them. Having said that, the ESRB serves a purpose, and honestly, they do a better job than the MPAA does at movies.
Having said all that, I think it's great to assure that vendors card/ID people, but broaden it's reach any further seems a little too "Nanny State".