A bureaucrat is defined as "an official of a bureaucracy" or, perhaps a little more judgmentally, as "an official who is rigidly devoted to the details of administrative procedure." Somebody who isn't just attentive, but rather rigidly devoted, to a boring office job doesn't really seem like one who'd appreciate a jaunty nickname; however, it does appear that some bureaucrats are actually called 'crats, to judge by this "crappy" T-shirt. (Crat sounds to me like a cross between "crap" and "drat," but either way you cut it, it does sound like kind of a drag.) Some people tend to get rather creative when spelling words like bureaucratic (too many vowels, I guess), whereas others prove a bit hasty when it comes to things like creativity. There were 30 cases of Crativ* in OhioLINK last time I checked, and 948 in WorldCat. Look all your spelling over carefully today—and don't be a "crat" and make your secretary do it!
(Caution sign by Michael Wilson, York, U.K., 2009, from Wikimedia Commons.)