I don't think it was as much a specialized deal for certain people as it was an experiment done by the board of tourism office in Germany to see if there was any interest. I'm unsure who is participating but I've never seen a single sign or indication that "VIP" cards are welcome or accepted by any businesses or that there are any benefits offered to card holders.
Let's ask some of the businesses who come on TTOL if they offer anything to cardholders; Nick @ Leverick? Paulfox @ Foxy's? Louis @ JR? How 'bout Elm, Myett's or Quito's?