Valve makes money when people buy or sell skins, which in this case is akin to buying or cashing in one's poker chips. There's also no way that Valve doesn't know that this is going on. While they're not involved in the strictest sense, they continue to allow this gambling to happen (by not policing their API) and make money by doing so.
I wonder what the legal implications are for valve here, vs the third parties that are facilitating the gambling. Surely the companies taking bets are also taking a rake (how else would you pay for your infrastructure/support overhead) and this is illegal in most of the US. Does Valve, by indirectly profiting from the wagering exchange actually bear some (legal) responsibility?
A better question would be whether NASDAQ or any other stock exchange is responsible if people use them to trade poker bets. What if NASDAQ was making a large profit on those exchange fees?
Valve is not only issuing the stock, but it's also acting as the stock exchange and taking exchange fees. It may not make them any more "responsible", but there is a whole lot of moral gray area there.
Valve makes money when people buy or sell skins, which in this case is akin to buying or cashing in one's poker chips. There's also no way that Valve doesn't know that this is going on. While they're not involved in the strictest sense, they continue to allow this gambling to happen (by not policing their API) and make money by doing so.