So, you want Microsoft to peddle their sub-par RTS to PC owners, but only PC owners who also have an x-box, and you're trying to stop ps3 owners from getting their hands on it by making them get some kind of code from x-box live. I doubt Microsoft would ever do that, since it cuts down their profits and, if the person had an x-box already, why would they want to buy the PC version as well?
Oh, and by the way, you can be a halo fan without xbox live, seeing as the internet (A wonderful PC invention) can also be used to play the PC version of halo online.