I know it's not a common opinion, but I believe that other than the rational argument you presented (which I agree with) I do think it's also a matter of values and mentality.

Yes Google is a big org, their business is problematic, and they do crap at times. But I think their mentality is much more less Machiavellian than Facebook.

I believe the "do no evil" as a compass, they might not always adhere to that as you or me may perceive it (after all, it is rather subjective), but it does seem to somewhat guide their actions.