I don't recall ever seeing him in the commissary, and who would forget?
With generic brand cigarettes sold in commissary for about a dollar each, packs were an effective unit of currency.
To cook the macaroni the commissary sold hotpots, which you needed a permit to possess and could only buy one a time.
mid-14c., "one to whom special duty is entrusted by a higher power," from Medieval Latin commissarius, from Latin commissus "entrusted," past participle of committere (see commit). Originally ecclesiastical; the military sense of "official in charge of supply of food, stores, transport" dates to late 15c. Hence "storeroom" (1882) and "dining room in a larger facility" (1929, American English).