Neither Mrs. Basket Case nor I have ever had a social media account (unless you count TF as one).
No Facebook. No Pinterest. No Instagram. No Snapchat. No Twitter. No nothing. Never had any of them, never will.
Still, we occasionally get comments that our pictures showed up on the Facebook page of someone we don't know. It's that facial recognition thing. Somebody we do know takes a group picture and posts it on their page. Somebody else we also know does the same. A third person who we don't know, but who is Facebook friends with both of the ones we do, gets a notice that "two of your friends posted pictures of these guys....you might be interested.
Now it's out there, and with the "status" attached to how many Facebook friends you have, our pictures end up in places we'd never imagine.
All that despite not only not having a Facebook account, but never having had one. Scary.