No, the docker program itself does indeed run natively on osx. You do not need to use boot2docker or any other VM.
You can't run any containers on osx, but docker itself runs fine as a client binary to docker running on a linux server. I use this configuration daily using a native osx docker binary on my workstation speaking TLS to a docker service running on a CoreOS server.
I agree that the reality of the situation is that it's abstracted away enough that the distinction isn't really all that meaningful.