Pretty incredible - especially with how little that a hardware product purchase has to do with a user's data. Imagine for a moment that google required people to have an account to access all their services - that they have the ability to cut you off arbitrarily across ALL their services for a TOS violation should scare anyone. Imagine if facebook cut your account and thereby ties to many of your friends and acquaint…
This is very imaginable. Facebook has never attempted to be privacy or user friendly; DO NOT USE IT. You are the only product they have of value.
In general, do not use third party login for anything personal you care about. It's not a password; it's nothing you control.