First, a prior poster mentioned the first sale doctrine, but the first sale doctrine does not apply to licensing transactions, only traditional sales. Because you are not purchasing the software, you do not have rights under the first sale doctrine.
Second, whenever you install this software you agree to an End User License Agreement ("EULA"). In this specific case, you have agreed to an EULA with the installation of both the Steam software and Modern Warfare 2. Both of these agreements contain region-specific licensing terms that make the use of the software outside of the intended region illegal. Valve and Activision are both within their legal rights to enforce the EULA that you agreed to upon installing the software.
If you are going to get mad at anyone, get mad at the CD key distributors that sold you these keys knowing it was in violation of the EULA. Demand your money back and be more careful about your future transactions.
Great excuse to make people buy the game twice.
sort of asking to be ripped off in my opinion, yes you can use keys not from steam to run steam apps but it is very important who and how you got them.
For exsample I bought UT3 at gamestop for $5 witch is at least $15 dollors less than steam charges. Since the makers of UT3 had made retail versions compatible I was able to get all of the content that all my steam brotheren paid $20 to get.
However I think that these people bought their not from a retail store, and not online from Steam or Activision; I think these people bought thier keys online from a differnet seller that claimed that thier product worked with steam.
Once again it is quite retarded to buy a Key to run a steam app if it didn't come from steam or the actutal Maker of the game.
AND generally it is dumb to just buying a key, instead of getting the game CD or directly from steam. *if you want it to run on steam*
I really don't think steam is at falt at all.
Just a bunch of consumers buying stuff that is too good to be true.
http://www.youtube.com/watch?v=gyeemtS1jII

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