This may a case of diversion, the browser market share for Chrome over other web-browsers is around 50%
, a figure that their business model may wish to increase more. Possibly, as Google see it as being more money in marketing - where with Chrome they know who you are, what you are, age etc and determine what sites you are looking at. To do this you need their Chrome browser, plus a few details about you when you log in. Having ad blockers will entice more Chrome usage and increase their browser market share. At the expense of some advertising revenue maybe, they will have greater data mining capability for marketing and selling the information.
A good business plan if their research results are correct.