If someone added you to a group you didnt wanted to be part of.......you can always remove yourself from that group....
That is a really good solution for those that know they have been added before the proverbial hits the spinney thing. I have my doubts that there wasn't a quick solution, like deleting the compromised account and starting over with better protection in place.
How many don't know they have been added yet? Just because you check your FB every day doesn't mean every ex-JW does the same.