Where there is demand, there's money ready to change hands. And boy is there a lot of money changing hands over Counter-Strike.
Mike Rose has a great piece up over on Gamasutra that looks at this scene, which at times can get a little shady.
There's gambling, rorts, bots and addiction. Perhaps most interesting, though, is a common thread running through many of his responses from those involved in CS arms trading.
In all of this, it's worth remembering that Valve is making a serious amount of cash through the marketplace. Multiple items are bought and sold every single second, and with the company's 15 per cent take on each transaction, you have to wonder just how much money the marketplace is bringing in.
When I was talking to my various gunrunner sources, I asked each of them the question, "Who are the biggest arms dealers of Counter-Strike: Global Offensive?"
The most prominent answer I received back? "Valve."