The bad thing about this article is that it only says you can't have flexible cord above the ceiling. Nowhere in the NEC does it say that you cannot install a receptacle above the ceiling.
We just built a mall here and in almost every store they had a device that had a cord on it above the ceiling. At rough I told them that they could not have an outlet up there and being good contractors they challanged me as to where it said it in the code book. I told them that I stood corrected that they could install it up there, but that they couldn't plug anything into it.