Bcuz the stupid guys are thehot guys or they are the "Bad Boy" type,in which girls like.They also date stupid guys bcuz they always want a Boyfriend (Most Girls,Not all) Or They just plainly want to get laid,or sick of being alone so they will date anyone.
Well I wasn't thinking that at all, but it's funny when a person says "I'm not ( ) incase you were thinking that" and its almost guaranteed to make the person think what you didn't want them to think.