“We will access, disclose and preserve personal data, including your content (such as the content of your emails, other private communications or files in private folders), when we have a good faith belief that doing so is necessary to protect our customers or enforce the terms governing the use of the services” - Microsoft
I place my bet on the fact that the thieves will get caught. Once they start selling the games and people try to use the game codes, police will start tracking down where they are coming from. If I bought a game and found out it was stolen, I would have no problem telling the police where it came from!
EDIT: A quote from the comments section in the article! lol
It isn't stealing if they were never going to buy the game anyway.