And Just FYI, The ESRB guidelines are just that, guidelines. The only reason stores won't sell outside the age rating is store policy to preserve their Image. It's not illegal in any way.
I could always prove that a given game wasn't bad by making a report about how it got it's rating from media scandals, unrealistic expectations, user generated content, and and the importance of context in a each games situation. usually along with links and references. Of course, I never tried something as bad as SR2, it's pretty brazen.
I once just started to explain to my mom how GTA isn't as bad as it's often made out to be (I wasn't even trying to get it, it just came up in conversation) She practically burst at the seams before cutting me off.