I don't really care about the rating, but the game. See, I wouldn't play Care Bears Deluxe if it were rated T, would I? But if SSBB was rated M, I'd still buy it. I wouldn't be able to go buy it by myself for 4 years, but I'd still get it.
It's very rare that a game is rated eC (isn't it?), but when it is it's not a game that would come off of shelves very often, you know what I mean?