I can understand those who wish to maintain their privacy. It requires a lot of operational security and consistency. There's also a limit of how private you want to be compared to what you want to do, so it's more of a spectrum than something that's more binary.
I'm at a point where I allow quite a bit to be known about me. I knowingly exchange my information for services - and I'm okay with that. I spent quite a bit of time on the opposite side of the spectrum but these days I let people/companies know more about me.