It's digital pimping. Google are fully-automated, mass-scale digital pimps. They pimp your eyeballs out to Johns who pay for the privilege of mindfucking you, with the help of an extremely sophisticated matchmaking and realtime auction system. In return, you get nice handbags (YouTube) and get your hair did (GMail).

Calling it "ads" and Google an "advertising company" is just making a vague allusion to what's really going on and does not carry the proper connotation of exploitation.