While I agree that a lot of the tourists are partly to blame for their situation, many are there through no fault of their own. If you remember, a lot of tourists were trapped after the evacuation had been ordered because the airlines had stopped running, and there were no rental cars available. If it was ME, however, I'd have been long gone out of Dodge before that happened.
Any reasonably healthy person can walk twenty-five miles in a day on flat ground. They had two full days of beautiful weather, in full knowledge of what was coming, and still didn't get the hell out of there.
-ccm