Neither do I. For that matter, I don't use it for anything where privacy is a requirement (be it for personal or for business/work reasons).
That being said, I've way too often encountered people for whom git oddly only exists in the form of Github, to the point of those being synonymous to them. The concept of a self-hosted repo seems totally foreign to them, and the only local git trees they have is what their IDE created for them in the directory of their checked out or created source project. It's weird, but such people exist… and lots of them.
I certainly not use Github for everything.