It's a horrifying fact, but sometimes people use the Windows 8 app store. Doing so is like plunging your arm into a toilet full of month old sewage in the hope of pulling out a diamond. Sure, there's a chance you won't emerge with a handful of unprocessed waste, but why would you ever take the risk?
Unfortunately, and much like various mobile app stores, the site is a breeding ground for scam versions of games. For instance, Darkest Dungeon designer Tyler Sigman warned on Twitter about an illegally sold version of the game.
If anyone has a contact at Windows Game Store, please share. Somebody is scamming DD by selling it (illegally) on there. February 22, 2015
Sigman follows by saying that if a player's copy of the game didn't come from the Steam or Humble Store, "you got scammed". The Windows store listing, incidentally, is for a 2MB download. Probably not an actual game, then.
Darkest Dungeon is by no means the only game being illegally sold on the store. The same "developer" has listed a copy of Lego Batman 3 (also 2MB), and SCS's Tomáš Duda points out multiple fake versions of Euro Truck Simulator 2.