I think 3D printing does have a potential to become a fad. Before we could print in color, we had to go to a photo shop to have our photos printed from a film. In this day and age, because we can print photos from our own printer at home, many photo shops have closed.
I would imagine that if we have the ability to print toys, dishes, jewelry, and other objects within a few minutes from our own home, people would prefer this option rather than having to wait for a few days to receive their shipment from an online store.
The bottom line is that I think 3D printing has the potential to change the way we purchase items.
On the other hand, there has been news stories about 3D printing holding the potential to create items for people with disabilities to allow them lead an easier life and these items would not be able to be created without a 3D printer.