Don't see the problem. If I have a website and want to block people by user agent string or IP address or whatever the hell I want, I can. Because it is my website. Maybe you want administrator access too, I hear Google doesn't share that with many people.
I personally think Google has been treating Microsoft too nicely. This is a company who's CEO wants to "f**king kill" them and plays cheap by randomly suing their partners. So quite frankly, most forms of retaliation are appropriate.