I also think it is interesting that Snow picked Mary to be called and that she said Margarat and then that is her name in the real world. I also like the idea that Charming’s name really is David in the real world. Maybe their names were somehow created by themselves when the curse happened since they all seem to reflect who they are in fairytale land. And maybe David was given his own real name because his memories were not full integrated because he was in a comma and they only happened later on. That is a good theory.