Products and processes are disclosed for defining at least one inventory group. This at least one inventory group includes at least two products that are available for sale by a vending machine. The vending machine outputs an indication of products that the at least one inventory group includes. The vending machine receiving, from a customer, a selection of a first product that the at least one inventory group includes. The vending machine processes a sale of a unit of the first product and a respective unit of at least one additional product for a single price.