I understand the frustration with this system, which I would hate to deal with as a customer. But when I read about it, I learned that you can decide to purchase the heating outright for a bit under $500, which I think is not an uncommon price for heated seats in many luxury vehicles (this was BMW). If a salesman framed it as "you can buy it outright if you want, or you can just buy it during the winter and save money", then I wouldn't feel so bad.

But if they deactivate the prepaid extras when you sell the car, that would be pure evil.