From most people's perspective I would think that has more than just novelty use. When I was at the Sands Exposition Center back in December of 2007 at the AutoDesk University while we were trying desperately to get our dog wash to take shape with the somewhat of a sculpting process --- I stopped at the good sized Z printer exhibit while they were demo-ing.
I was in communication with an out of state service that based on a CAD drawing would do a scaled down model for the custom tubs to keep the costs down before going into fabrication. If we had been more confident of our sketches it could have helped but as it turned out we wound up playing with actual size large pieces of cardboard to convey what we had in mind.
Depending on the project or the part that needs to be fabricated --- it could be potentially cost effective, practical & in other ways worthwhile. Materials needed is definitely a factor. Like any other business
transaction it is a good idea to get some firm quotes & cover the details enough --- otherwise costs could get out of hand. It could be a real adventure!
Hopefully, some of the more engineering (like Ghetto if I remember right) or others amongst us can share some other experiences on what you posted.
MJ