Agreed.
Though it seems like the normal rules are thrown out of the window inside the penalty box. It usually takes a pretty clear foul for a penalty to be called.
I think, the Ghana players hurt their cases by overplaying.
Even if there was some limited contact, the ref was turned off by the theatrics...
FIFA referees officiate games as if they are frightened of being blamed for any goal. Therefore they do everything in their power to limit scoring opportunities, which always makes them seem biased against the more attacking side.