This is probably the biggest problem with a sharing/renting economy.
Manufacturing has gotten to the point where producing an object is so inexpensive, it's cheaper to buy than rent. But why should that be? At any given production cost, why isn't it still cheaper to produce fewer and let multiple people use them, either via a renting system or something else? You're making fewer objects and still satisfying demand, so why doesn't this save money?
The reason is the labor and real estate costs of administering such a system. You need people to staff the rental/sharing agency. You also need a conveniently-located (and thus expensive) building where people go to pick up and return the objects. Or, if you're doing delivery, you can choose a more out-of-the-way location, but now you're paying the labor cost of drivers.
Because the overhead of running a sharing system is so high, it's actually cheaper most of the time to allocate one of each object to each person, except for the most expensive objects.