I've been running Firefox with Ghostery and NoScript for about four years. I know the consequences.
I only access Facebook from a VM or an old smartphone with no SIM. That's because browsers are designed to circumvent my attempts at privacy and to facilitate the ends of third party cookies.
Using a Git analogy, there is no reason for a single cookie repository. Suppose foo.com injects a third party cookie from bar.com into my data stream. It could sit on the foo.com branch of my cache, so that when I visit baz.com, it does not know about the bar.com cookie, and injects another one [which sits on the baz.com branch of my cache].
When I want to have a single bar.com cookie for foo.com and baz.com, then I merge them and let bar.com sort out any discrepancy. To put it another way, there might be a few websites where I wish to allow a shared persistent Facebook cookie, but I don't want to share that information with every website with a LikeUsOnFacebook widget or share all my browsing with Facebook.
But browsers thwart that process and facilitate tracking. It is by explicit design that browsers break the web when there are attempts at privacy. They are designed to mislead users and be truthful to remote websites rather than vice-versa.
