I think the military guys often don't install thrust reversers (they even uninstall them sometimes) unless they really, really need them. Might be a cost/inspection time aspect and yes, the E-3 does not come with such things in rw (from my knowledge).
Since the payload and passenger load on the E-3 doesn't really get high (or changes like on a Freighter or Passenger Transport), the only big load will be the fuel while those planes operate from very sufficient runway bases.
But that's just guesswork of mine, never mind.  :)

So, in my eyes, Mark is perfectly right with applauding to the fact that CS modelled this "lack".