Money is not an object, it's a concept. Also when you forge money you devalue the whole currency therefore subtracting it from everyone. You could argue that pirating a game devalues it, but then I ask you is the game that you paid for any worse because Joe Schmoe made a copy?
It never was, only a corrupt judge can reach that conclusion. Stealing is subtracting an item from one person and adding it to another person, if there are two copies of the item then it's not stealing.
German shepherds love to carry random stuff, I know one that brings huge rocks inside the house.