jamyskis: While I agree that this is rather ridiculous, if I may play Devil's Advocate for a moment:
Hammerwatch is a great multiplayer title to play with friends, and four copies of the game for $8 is actually not a bad amount, as it then boils down to $2 a copy. I suspect a lot of the 'buyers' are simply groups of four people chipping in together for a $2 copy instead of having to pony up for the full $7 for a single copy.
It would certainly make more sense, as I really cannot imagine anyone in their right mind paying $7 for a game that has been half that price pretty much everywhere else (then again, PC gamers...)
I think the problem is calling this a "bundle". I'm pretty sure people would have bought it if they just made it it's own sale.