The difference is with the book your alternative is to not sell it back and getting 0$, assuming you've extracted all value. In the case of the car, you can ch

The difference is with the book your alternative is to not sell it back and getting 0$, assuming you've extracted all value. In the case of the car, you can choose to not sell it, and use it for driving instead. The incentives are completely different. You're comparing a scenario where they have you by the balls with a case where both parties are more or less equally powerful market participants.