I have a friend who wrote his car off in a prang, yes his fault, but you can't pick when and how you have an accident and the company hit him up for the rest of the cost of the new car because the insurance only covered the cost of the car, not the rest that you would pay for rego fuel atc, he had an enormous bill at the end.
I have also got friends who've been hit up massively at tax time because they haven't done the required amount of kms.
Saying that though we're seriously looking at it too.