"Friends-of-friends"
My stuff doesn't go to them unless I post publicly. But I know many of them. They're just not MY friends. There are some folks who'll accept any friend request, and that's not smart. Seeing as I can't watch what other are doing, my feed's visible only to friends.

There's one guy (American) who's been a member of a BNP based group for years, and will not believe that's what it is, because it's ostensibly about "folk" music. He once friended a clone of a mutual friend and told me I was wrong after I said so. You learn who's potentially infections and who's not. I haven't unfriended this guy, but he's on my "restricted" list, meaning my posts don't go to him unless I set them to "public".

There's a learning curve.
Often, what people complain about is their own lack of knowledge about what they can do. I've figured some of it out, but there's still probably more that I DON'T know.