I think what Daniel is saying is that no world has non-gardener moles, so maybe this is a clue to the next world that KI will release. One with moles, just as Celestia has Crabs that were in the Selena Gomez quest a few months ago and the bear in Old Towne that gives you a preview of Grizzleheim.
Could be. But maybe KI just figured moles made the most sense for gardening. :)
Well, if we think of it, we don't see any other cranes but Mr. Lincoln; no other unicorns but Diego, and only Reginald Baxby is a zebra. And Greyrose is the only non-healing fairy we meet.
There is most likely a world of sentient unicorns, cranes, zebras (and lions and tigers and bears, oh my!) - and we have been told by Greyrose that she comes from an entirely different world than Wizard City...
The moles might just be from a part of one of the known worlds that we haven't seen yet. After all, moles usually live underground - and we only be seeing Harley, Farley, Charley and Marley because Moolinda pursuaded them to teach us young students the secrets of growing plants.
For all we know, the Moles might be from an underground "world" hidden beneath Wizard City or Mooshu. Or even Dragonspyre - where they can slowly start to return to the surface, now that the Dragon Titan is finally asleep for good.