It's not just that they're expensive markers of conspicuous consumption, it's about exclusivity. Exotic car manufacturers like Ferrari intentionally make fewer cars than the market demands. Only "special" customers are even allowed to buy them regardless of price. Ownership, especially of the higher end models, marks a consumer as a member of a high-status exclusive club. (I am not claiming that this is rational or sensible, but it is an effective marketing strategy for luxury goods.)