> Not true. They make money by monitoring their customers' online activity and using the data to target ads, which they sell to advertisers. That's only half t

> Not true. They make money by monitoring their customers' online activity and using the data to target ads, which they sell to advertisers. That's only half the truth. In real-time bidding system, personal identifiable information is actually sent to advertisers at scale. It's not directly selling the information, but advertisers who make generate too little revenue can't participate in those RTB platforms, so there is effectively a minimal amount that advertisers pay per potential click, so close enough to actually selling the data.