Every google product exists to encourage people to see more ads, even if he product isn't showing the ads.
I encourage anyone to point to a google product that isn't either selling ads or trying to get people to spend more time on the internet so google can sell them more ads.
How do you figure? There's no offramps from Drive or Docs into Search as far as I know. Are you saying that because they're subdomains, it somehow works to get you to ads?
Docs and Drive want to sell you storage and collaboration capabilities. Not ads.