Yeah, why would HTC agree to something like this? Sounds like Google got a hell of a deal getting to pick which engineers and IP they want without having to buy the whole company.
Build a local team that a foreign project customer would have trouble hiring directly (due to being foreign), let the team prove itself on the project, hand them over for a massive fee. As long as the project/team customer is willing to pay good money for this it is perfectly fine business.
One time payment instead of continuous revenue from future projects. The difference is that the one time is money in the bank, whereas future project work is merely a possibility that might fail to realize. In the end it is a question of the right price and I get the impression that this one has been very generous (even after discounting for the IP.
