"A rap song came on and it made me think, "Should I just give up, get a rhyming dictionary, talk about bitches and hoes and the hood, and just make music on the computer.""
So what you're basically saying is that you heard one song out of a massive genre that's been around for 37 years and based all your assumptions of the genre on that one song you heard when you were already in a bad mood?
Yes, rappers can be intelligent. The real question is, are you an intelligent listener? And I think the answer is no, you are not.
I'm not sure how an abstract concept like a genre of music can be intelligent given that it has no neurological abilities in and of itself.
Yes, intelligent people listen to rap. Maybe you should try it: you might learn something.