Dealerships aren't allowed to "sell" warranty work. If the customer isn't complaining, it's not a warranty issue. Prevents warranty fraud.
This is incorrect. Whenever the vehicle is in the shop for any work it is the duty of the technician to inspect the vehicle for any defects or damage. If somthing is found that is covered under warranty they get an ARA(Additional Repair Authorization) slip signed by their shop foreman and the repair gets added to the ticket.
I am an ASE master certified dealer technician BTW.