I can understand their motivation in wanting to catch hackers who posted screenshots to websites and whatnot. That said, it seems like a big security risk to attach the account info to something that's posted publicly. I'm sure there is a general ToS clause that covers their ass but it still seems pretty dumb.
Apparently you can defeat it by using a different screenshot quality or compression method.
Playing: The Witcher 3, Bloodborne, Secret of Mana Watching: X-Files, Mad Men, Mad Max Fury Road