The analogy falls down because stores generally don't benefit a great deal from having products in their store except insofar as the money they make for the sto

The analogy falls down because stores generally don't benefit a great deal from having products in their store except insofar as the money they make for the store, or occasionally the money they'll make by consumers buying other products in the store (in the case of loss leaders). The iOS app store could be 100% free apps, or even 100% apps that Apple doesn't get a cent of, and Apple still benefits from those apps existing.