You're right, it's nice to have some advantage for a bit of privacy abandonment. The problem with privacy: Its global level goes to the lowest willing member of the human species.
You're ok to give away some privacy, you get a TV with face-recognition. You get some advantage. I like my privacy. I own no phone, no tv, etc.
I come dine with you. I get face-recognized by your screen, parsed in whatever server, located, and spamed scary relevant ads about skin problem. And I get no advantage for it. It's like the privacy-concerned guy who used it's own mail server, and discovered 80% of his communication were on google server cause he sent mail to gmail users. The much one person is willing to abandon in term of privacy the most we all abandon un-willingly.