In this case they didn't remove the app from the users' devices, they “removed Alternative Distribution functionality from iTorrent’s Developer Portal without any warning.”

So they revoked the right of the developer to publish on other stores, and don't allow publishing that app on their own store.

Beside of those apparent "government sanctions-related rules in various jurisdictions" cited as reason by Apple (whatever that means), they now demonstrated that they still have indirect control over the offering of ALL digital markets.

So regardless in which market you want to publish, you still need to remain in good standing with Apple.

Combining that with Apple's ability to observe the install-base of iOS-devices it's quite a conflict of interest. (The least nefarious being Apple courting successful apps from other stores to come over to Apple)