Well, it might be the case that it is. Has Clarkson denied that it was aimed at them? Regardless, there definitely is a type of interpretation going on, and ultimately a choice, as to what someone finds offensive. It might not be an easy choice depending on how you've developed but clearly it's a choice when you see that some of us aren't offended and some of us are. We're not born knowing words and cultural conditions (prostitution and their murder) so our response to them is conditioned. Is there a usefullness to being offended about such jokes? Not that I can see - you just waste your time be experiencing distress at the words of others. It's only when the words relate to some occurence in the present or future reality that it might be worth being offended by them. For instance the words, "I'm going to kill you by stabbing you to death one thousand times with a toothpick" might be worth getting a bit pissed off about in order to possess a more supportive emotional state in order for defending yourself against such an attack. Even then however, you'd probably be better off by maintaining your cool and lack of concern in terms of achieving a decent concentration.