@deftonian
You are right except you ignore the fact that the cut material can be easily reclaimed. Some shavings take a lot of energy to recycle and reforge, such as aluminum. Plastic on the other hand is nearly effortless to remold, which is all 3D printing can work with anyway.
For the price of this printer you could get a light duty CNC router that could handle plastic and other materials like wood, and perform other useful tasks like engraving.
For some reason 3D printing is being pushed on us like it is some kind of technological breakthrough that will change our lives forever. That's just not the case. The only real beneficial applications of 3D printing would be with the space program where weight is at an absolute premium. Of course it might be easier to solve the weight problem with fusion or anti matter propulsion than to create a 3D printer capable of altering metalurgic properties on the fly and working on the subatomic level, that would be required of such a device.