An interesting point Sapper.
Not an attempt to justify the difference, but ultimately the reason for the difference probably lies in the answers to the following questions.
1) If we don't let the Junior Officers/Junior Ranks 'let off steam', what happens?
2) If we do, etc....?
After the Cold War, when an ever-increasing number of the Rules suddenly started being applied to the letter, I left early, as did many others. Your rules, but my life.
Did occasional flagrant disregard for Rules lead to a breakdown in discipline among Junior Officers when it mattered operationally? No, not a bit of it.
I can recall several occasions when a look at the Mess at 0700 hrs would reveal an apocalyptic scene, yet by 1159 hrs the place was spotless. Once this involved, among other tasks, relaying an entire croquet lawn (finding that much grass on a Sunday morning in rural Wales is, pardon the pun, sodding difficult). Furthermore, on no occasion were the Mess staff expected to clear up after us - we did it ourselves.
Certainly on operational squadrons there were times, especially on detachment, when our JR were supplied with copious quantities of alcohol and left to their own devices, with ample time for a clear-up in the morning before any inspection.
What is your perspective from the JR side?