I recall when Coca Cola went up from five to six cents a bottle back in 1944.
As a member of the 45/56th Field Battery (R) we used to assemble at the Armories once a week for drill, etc. under the capable leadership of men such as our Commanding Officer Major "Al" Perry, Regimental Sgt. Major Fred Langley and Battery Sgt. Major Percy Wilson.
There was a "Coke" machine in the Armories that stood against the east wall and it was there that we used to get ourselves a bottle at the sum of five cents. Without warning, pop went up one cent and it caused quite a dilemma since there was no slot one could put a penny in to make up the difference. To overcome this problem it was decided by the powers that be that every sixth bottle would be an empty thereby it made up the difference in the price increase.
This scheme didn't work out too well as the fellows would stand around innocently looking for someone to drop a nickel in the machine and come up with an empty. At this point there would be a rush to get to the machine and thus get a full bottle for a nickel.
Eventually, Major "Al" Perry devised a plan that would resolve this problem that he receiving many complaints about. He ordered the custodian of the "Coke" machine to place empties in a variety of combinations such as perhaps three empties, or two, or four, etc. in succession thus eliminating the plan behind waiting for someone to get stuck with an empty and rush in to get a nickel "coke".
At first the guys didn't care for the Major's plan but eventually they remarked that "Al" was a pretty darn smart guy to think of the idea and, in the final analysis, the money the machine was taking in still balanced right to the cent.