Re: @Wiltshire
Wrong... go to the FB link on the article page for this any other story... and then click the FB link. You'll see this:
Log in to use your Facebook account with TheRegister.
Yes, you'll have to be logged on to Facebook if you want to use the button to share the story on Facebook, same as the other "share with …" buttons next to it.
The OP was talking about the footer Facebook button, which along the others are mere links to The Register's presence on those platforms.