Niko_JimsThat would imply that Valve cared about anything but money at this point. They get 75% of the cut, that's money they are losing. They are a business, they will not stand for that. The whole debacle with them and the UK/Euro law about game refunds proves this.
Let me phrase it differently then. Valve cares about their money. If they remove refunds, a fuckload more people will stop buying mods, on top of the ones that already won't buy them. It's in their best profitable interest to implement DRM to protect purchases, rather than fuck up those purchases in the first place. I'm not a fan of it any more than you, but that's what they'll do.
Keywords there. You also forget that Skyrim "cosmetics" also have stats/rewrite in-game models. TF2 hats do nothing, and are new models added to the game after being reviewed by Valve.
Stats are irrelevant in a game with a console and constant cheats without multiplayer. That means nothing. If it implements new functionality, like awesome new spells, cool. But just stat rewrites aren't enough. As for rewriting ingame models, they don't really. Modifying ingame models is about as easy as making items in TF2, if not easier because TF2 is far more broken.