That's really odd to me. My Facebook friends are people I know from real life. Every so often I get random accounts (usually attractive women in random locations with no mutual friends) trying to add me and I will report them as spammers.
>>Middle+(OP)
I'm the same way, but the platforms incentivize the collecting of friends and have like a decade+ of gameification features to promote it.
>>heavys+JD
Perhaps Twitter or Instagram, which seem to involve people mixing their personal lives with strangers (idk never really used them), but regular Facebook doesn't seem to be used that way by anyone I know.