Well, anger may lead to various possibilities. I had reverse engineered certain cloud storage service client protocol when I was told there won't be any cake (properly functioning GNU/Linux client software customers were promised for a long time) for me and I have to fuck off. And I had not published it only because RE laws in my country seem to be totally messed up - they literally say I can't publish my findings. Wish I'd live somewhere saner.
Still, as I believe, quite a lot of people use Hangouts. Sure, there must be a hacker somewhere who's upset enough to mess with the software.
Maybe because Hangouts was created as an unwelcome product eating a completely functional service people liked.
Nobody wants to invest in a service which just told you to fuck off.