I'm getting the same exact items when doing certain achievements with both of my accounts. Checking my Inventory gave both accounts -33% Valve, and joining the Group gave them 2 pieces of Coal.
It's weird, because some of you guys got different items for those achievements, right? Is it tracking my IP and giving me the same items becaus of it or something? I still don't see how you couldn't farm coupons/coal/games with infinite accounts either