But the thing is, the free apps can also just use the pre-existing distribution mechanisms. Of course, it's giving Apple the leverage to say, "see? No one* wants to use the alternative stores!", but also think that if you have an entire team with experience and established relationship of App Store review shenanigans, you just continue to use it.
It's more interesting about the upstart companies who might get big one day.
There a free apps that don't exist on iOS simply because Apple doesn't want them in their store. These apps are not necessarily malicious, but may contain content that Apple wishes to censor. If Apple continue to say what is and is not allowed on iOS, then nothing/not much is gained by this regulation.
Edit: Of course, eBay will likely continue to be allowed.
It's more interesting about the upstart companies who might get big one day.