story
Chrome kicked off the browser performance wars, especially javascript. A fast and performant web was important to any strategy Google could have had, regardless of their status as a good or evil company.
But man, Chrome sure got good fast.
http://www.cnet.com/news/browser-war-centers-on-once-obscure...
That it's a performant browser is a side-effect.
My argument is that nobody would have put that data online in a slow and sucky web. If you think Google wants full control over the audience, surely they also want a large audience.
(Note that I do not think that Google is evil. But if they were, I don't think they would need chrome to get most of that information anyways, given all the other ways they are collecting data. Sure, there are some corner cases they would miss but I don't think the incremental coverage would be worth the effort.)