Eminem's Secret Strategy?

I've been listening to Eminem a whole bunch recently, but instead of his newest CD releases Relapse and Relapse:Refill, I've been spending much more time listening to his older works. Why? There's no doubt that some of the hooks and beats on Relapse are catchy, but when it comes to music for me, lyrical meaning beats skimming over a song for cheap, quick thrills. Have a look at the lyrics for "Insane", "Same Song and Dance", or even "Bagpipes from Baghdad". Pushing the limits of lyrical content is what Eminem does best even if he does find himself in lawsuit after lawsuit, but these are way too extreme for even the most mature ears. I obviously can't listen to any Eminem with my mom in the car, but it shouldn't be a big deal to listen to his new songs with my girlfriend who's the same age as me. It is. I can't help but feel a little bit awkward when "Insane" comes on, and Mathers blatantly raps about his step-father raping him. The lyrics and rhyming isn't even clever, it just feels like a constant string of profanity in my ear. So why does he do it? Does he really use his musical talent to express his feelings to other people, or is it one big ploy to grab the attention of teenagers and media with unbelievably vulgar language?