Great question. Only application I've ever seen it used is by the mx department. Who finally no longer seem to want it used as DTG for our flight logs. But it is still the flight date format used on their hard paper copies (when used uncommonly). I think it is more likely a holdover from this, before we had computers, and always filled out the DD form post flight. Mil loves a good tradition, even when it no longer makes any sense. Most/many Navy aviation squadron maintenance control desks still keep a flip card Julian calendar prominently on the wall for this reason, which is total insanity in my mind.