Yeah, social media is truly bizarre in a myriad of ways, one of them being this: When did people think they were invited to be super weird? I've been thinking a lot about some of those old fashioned books on manners, and wondering if they could (ever) be translated to social media. Probably not.
As for your friend on FB, I have friends like that too -- who are now passing that behavior on to their daughters. Really heartbreaking in a way.