Withdrawal of an automatic subscription should delete all autosubscriptons
1. An automatic page subscription is created by mistake
2. The automatic page subscription is turned off
Everyone is still subscribed to the page but can unsubscribe
Nobody should have subscribed to the page anymore
I agree with Sven, we use this function to suggest pages to users...
Unfortunately it is not a no-brainer. In the case of a newly created page it would totally make sense to remove the subscriptions for everyone but what if this happens to a page that already had subscriptions? Ideally you would remove the subscriptions that were added by the auto-subscription feature but leave the subscriptions that were created manually by the users themselves. Unfortunately we can't identify which is which.
Another use case: What about pages that existed for quite a while (with auto-subscription for everyone) and users got used to be subscribed to this page. Now an admin decides that users should be able to unsubscribe from this page manually. If everyone was removed from the subscriptions list of a page when auto subscription is turned off - one could get confused why he or she is not following this page anymore.
I understand the use case you are describing but there are also reasons to leave it as is.