Almost posted that last meme myself. The woman who posted it in the Facebook group I'm a member of was entirely serious, and so were several other people who joined the discussion on her side.
My god, what an experience skimming through that group is. To be fair, most of the recent comments about that meme are dissing it - no doubt not actual group supporters.
Btw the girl who posted that Civil War image grew up in a well-off midwestern suburb and has pretty much stayed put. I would be shocked if she ever knew a black person beyond a casual basis.