Except the insurance company. What you suggest is insurance fraud. I thought Audi drivers were above that sort of thing. It may be difficult to change it back to standard from your hospital bet!
Think insurance fraud would be the least of your worries if you end up in hospital! I expect they would ask for the difference between the cost of the two premiums to be honest.
Are Audi drivers special in some way? Do they not commit crimes due to their choice of car?