I think a perfect example of this is email. We used to pay for email; it came with our Internet service. Then they started offering free email services that would show banner ads in a webpage. Kind of annoying but good for people who didn’t have regular access to email in the dialup days, or eventually we realized it was convenient so we didn’t have to change our email everywhere each time we changed our ISP. Then Google started actually scanning our emails to give more relevant ads. They were less obtrusive, but we were giving up more, but we also got a lot more email storage in return and it seemed okay. Now most people use a free email for their primary. Our ISP (probably) still offers an email address with a small storage option, but who still uses that? People gradually gave it up without realizing what they gave up. Now it seems like you have to pay even more on top of your Internet access to actually get email privacy.