Ditto, I'm all about leaving the campsite better than I found it. Just my nature and common courtesy for the next person.
I agree though with olsonm. Although we use a table top grill, I have never seen any tables burnt like in these pictures at the places we have camped. Common sense and care should prevail when using others resources...but then again common sense / courtesy is becoming more obsolete, in general.
Still, we leave our camp site in better than found condition and that's all that matters. Just keeping it "old school" here.