All I can tell you is that I had a Samsung Vibrant for almost a year and a half, also with what you would call "cheap" plastic, and when I sold it, it looked brand new, like it was never used. Not a ding, dent, scratch, or imperfection.
As is my Droid X. Perfect condition. Naked since launch day. Moto does make a great phone even if they are ugly.
or it came out of the box like that and you didn't notice it at first, or yours was defective.
I am not beyond admitting this is equally likely. However, once you notice a nick in the plastic next to the screen, it is impossible to un-notice it. I tried to. BTW, it is very hard to describe where the nick is. It is on the front of the bezel (looking at the screen) on the inside right next to the black of the glass. It is where an impact could not have occurred unless it was from an angle that would have also impacted the screen.
I am done with the nick stuff. It happened, don't know how, never happened on my DX.... yada yada yada. Lesson: you guys should get a case for the Samsung Nexus. I had one coming... tomorrow. Oh well.