And what if I tell you that Tor was made by CIA... Now it is developed by geeks and nodes, relays and bridges are sustained by privacy geeks. They need it for some of their operations. I bet that this is the very same reason why Gavin was invited to CIA - they were looking for anonymous global payments system for their operations so they invited main developer to consult it. Maybe they are using Bitcoin for a while 

Tor was originally designed, implemented, and deployed as a third-generation onion routing project (http://www.onion-router.net/) of the U.S. Naval Research Laboratory. It was originally developed with the U.S. Navy in mind, for the primary purpose of protecting government communications. Today, it is used every day for a wide variety of purposes by normal people, the military, journalists, law enforcement officers, activists, and many others.