But you really can't just "go to the mall next door", since your faithful customers cannot follow you and your entire merchandise has to be remade from scratch.

For that reason, no real mall-owner ever can even dream of extracting 30% from every sale. Why can Apple/Google/Sony/Microsoft/Nintendo get away with it? Because they don't suffer competitive pressure in the same amount. Most of them are effective monopolies in their segments, thanks to network effects, so they can get away with the worst type of feudal rent-extraction.