goudie:-
With regard to a trading monopoly, every Sqdn I served on had it's own coffee bar and refreshments 24/7.
I suspect it might be a question of degree. An MRT Squadron in the 60's would have had perhaps some 180 aircrew (manning was approx 5 crews per aircraft, 6 man crews, 6 aircraft). I don't know how many groundcrew would have been on strength, perhaps as many again? That was why it was a business for a contractor rather than a DIY job in the boss's view. Mind you we did have a Coca Cola fridge upstairs that dispensed cold bottles of the stuff for so much a go. I remember that as I had to keep the damned thing replenished!