Hate to be a cunt, but, nope!
http://www.computerworld.com/s/article/ ... ven_onlineEurope's highest court ruled on Tuesday that the trading of "used" software licenses is legal and that the author of such software cannot oppose any resale.
Has that ruling ever been upheld ? more license keys are now bound to an account, I've never seen an ability to unbind the license key in any gaming software or Adobe product (photoshop mainly).
Most downloaded content games don't even come with license keys these days, I haven't received a license key for the last few purchases I have made, it just worked as it was purchase through my account, how can I re-sell something that I never have ?
Now to sell 'my' copy of the game I'd have to sell my account with all my other purchases bound to it, which is against the EULA and TOS of that company, which if caught they can suspend and ultimately close that account.
If you want to take Blizzard or Valve to the EU courts, to sell a '£40' game for £20 used, good luck.