This would be like if there were one single store on the planet and if they don't want to sell your shit everyone just says, "That's their right, shouldn't have gotten into the business of selling things."
But there are 2 stores, and you make the choice of packaging for one or the other. You can also make your own store, if you want. (In this analogy, that is. You cannot make a store inside a store, that’d be silly.)
Basically, you can still sell on Android, or, make your own phone/mobile operating system?
Shopping malls owned by supermarket companies do exactly that. A hypermarket in the centre, owned by the supermarket company itself, and hundreds of smaller stores around, operated by others in the same building.
