Neither of us knows this, so we may as well stop arguing about it. What we do know, is that running the servers and hiring all those engineers costs money, and their revenue is almost entirely ads.

I don't think it's a stretch to assert that users that engage with and click on ads are much more valuable to Google than users that don't.

Whether the users that do neither contribute positively or negatively to the bottom line is an interesting question. I suspect they're a net negative, but obviously you disagree.

Google themselves probably know the answer, but I doubt they're telling...

Aside: a supporting data-point for my gut feeling here is that AdSense has always contributed much, much less to Google's revenue than AdWords does. The difference between the two gives a clear indication of how capturing user intent (searching for products) completely dominates how valuable (=effective) the ads are, and is much more important than all the other tracking combined. Google could probably turn off all the tracking and still make tons of money. Some numbers are here: http://www.investopedia.com/articles/investing/020515/busine...