Or they're a way to put dibs on a spot in line to decide whether to buy the car, and the size of the deposit exists only to ensure that people are minimally ser

Or they're a way to put dibs on a spot in line to decide whether to buy the car, and the size of the deposit exists only to ensure that people are minimally serious. In which case, there is some signal to be extracted from people's willingness to give Porche an interest-free loan on the deposit money.