This really is an important point.
Somehow in this new age of technology companies we have forgotten that corporations, in the long run, will always converge on what is most profitable, regardless of the values of their founding team, who will eventually retire or have their influence diminished.
For that reason, I always pay more attention to a company's incentives than I do what they say about values. If a company derives the vast majority of their income showing me targeted ads, I can expect that that will take priority over any notion of privacy, and we all know that privacy is the bane of targeted advertising. Unless there is some seismic shift in Google's core business in the next several years, we should only expect more moves like this.
And as we head into the new era of "intelligent personal assistants," let's keep in mind which companies are pushing this most aggressively: two ad companies and one that wants us to make it easier (perhaps even not a conscious activity?) to buy things from them. It does not take a lot of imagination to see what these assistants are most interested in assisting us with.
That's why, for all of the valid criticisms of them, I still use Apple products. I'm just more comfortable with their incentives, which are, as of now, mostly to sell me shiny new hardware. Sure, this has led them to do some things that annoy me like lock down their iMessage platform so I can't use it to communicate with my Android-using friends. Still I'll take that sort of behavior over a wholesale disregard for my privacy.