3d-printing is just another tool. It makes it easier to make several identical puppets and parts for animatronics (movable ears, eyelids,...). It's not cheap, it's not fast and most materials can break easily if they are printed too thin.
3d-printing puppet heads is like trading money for time - I can do something else while the 3d-printer prints the part. This only works with a reliable 3d-printer and well-constructed 3d-models.
My puppet related tutorials:
http://puppet.tioh.de/