Fine, so instead of Craigslist Guy, let's use Home Depot, where I shop often. Just shopping there does not imply my consent to them tracking where else I go and shop throughout my day. Merely having an account somewhere or regularly doing business somewhere should not imply consent to tracking and data collection, to which I must opt out.

ADD: I probably have 100+ accounts at various sites online. Do these guys all get free passes to collect data and track me because I happen to have created an account there?

If you opened a credit account with Home Depot or had their loyalty card you'd be literally consenting to more tracking. That's the difference between an account and a one off transaction.

Facebook certainly operates outside of even this rather liberal framework so I wouldn't defend them wholesale. However I don't like false equivalencies.

It's one thing to track me on facebook.com where I signed up, another to track me on blogs, newspapers and everywhere else.

> Its the difference between seeing someone multiple times and saying hello to a stranger on the train.

It goes further than that, as it affects other people too.

See also: Eben Moglen's talk about how privacy is ecological, not transactional.

http://snowdenandthefuture.info/PartIII.html

Facebook also spies on people who have never used the service.