Hmm. I didn't intend for them to track me. I didn't know their 'like' button was on the website I intended to, and then in fact, visited. I intended to visit the website, I didn't intend for facebook to visit the website with me.

The website author apparently intended for facebook to visit, but I was not privy to that information. That's like me attending a meetup. I wanted to go to the meetup, but if my ex was there, and I knew that ahead of time, I wouldn't have gone. Now my ex has information about me I didn't intend for said ex to have.

I'm not sure if I've convinced myself that the 'like' button is legal or illegal now.