If it hadn't occurred to you yet that Facebook cares far
  more about the "Like" buttons that you don't click than
  about the ones that you do -- there you go.

I've been telling this to people since ages. These stupid Like buttons are an infestation, and exactly the reason why I care so much about Facebook's privacy policies despite not being registered on it - it's just not as simple as "not having an account". This goes for the other networks, too, by the way.

Besides, this solution with the two clicks is very clever, and privacy friendly. In addition, it speeds up page loading. It speaks for itself that the only measure Facebook has is trying to sue with a very broadly formulated policy, which I doubt applies in this case anyways:

  if such use could confuse users into thinking that the
  reference is to Facebook features or functionality.

Well duh, it is a Facebook feature/functionality.