One of my cats once escaped out of a window at ground level (he managed to dismantle the netting while i slept, it's the only time any cat of mine managed to do something like this), and the big explorer promptly got scared and hid in the insides of a car parked directly outside. He didn't get hurt (except his ego), but was full of oil and dust from the breakpads. That's the only time i thoroughly bathed him (and paid the blood price). You are right of course that bathing isn't something you should do just because, but if the cat is actually full of very unhealthy stuff, i want to prevent him eating all of that while he grooms himself.