sutlers

Vivandière is a name for women who were attached to military regiments as sutlers or canteen keepers.

Profiteers, but there may be other more specific terms. Profiteering can exist in peacetime as well as war, when greedy merchants see the opportunity to sell necessary goods at exorbitant prices, knowing that their customers have no choice but to pay it. During the American Civil War merchants were licensed to follow the US Army and sell goods. They were called sutlers; some of whom were honest merchants, and others of whom engaged in ruthless profiteering.

A sutler was a merchant willing to take the risk of venturing into the field with an army in order to sell food and supplies. Also called victuallers, although that term tended to refer to merchants who supplied the army while in its barracks or fort.

The sutlers were like traveling stores. They sold playing cards, knives, coffee, tobacco, soap, and various other items.