The ubiquity of rental cars are one of the great advances of human civilization. Think about it for a moment: you sign your name (and if you’re a member of a rental car company’s membership program, not even that) and you are given the keys to a vehicle that costs usually $20,000 or more. No questions asked. That’s a real hallmark of trust in markets and highly developed institutions.
I’ve wondered sometimes how we should treat the costs of locks.
On the one hand, you buy a lock, that is counted as part of GDP. Well-used locks genuinely make you safer; they add to your welfare function. A world in which you are allowed to have a lock, and can afford locks when you need them, is for you a better world than one in which you are not allowed locks, or they are priced out of your reach.
On the other hand, a world in which you need a lock is not as good a world in which, all other things being equal, you do not need a lock. If you could rely on something free — magic, social conditioning, hardwired biological morality — to secure your places and possessions, then you could save all that lock money and spend it on something else, raising your utility even further. So in this view, each expenditure on a deadbolt is a deadweight loss, a sign of a social and economic failure, a waste of resources that could more profitably be employed for something else.