A commodity registration apparatus includes a check-in terminal, a sensor group, and a management terminal. A processor of the management terminal is configured to track movement of a shopper and store items using the sensor group. A first commodity list is updated to include a first item when the tracked movements indicate the known shopper has selected the first item for purchase. The movements of any unidentified shopper are tracked. The processor updates a second commodity list to include a second item when tracked movements indicate the unidentified shopper has selected the second item for purchase. The second commodity list is associated with a provisional identification code. Commodity registration data for settlement processing is generated using the first commodity list unless the unidentified shopper is later identified as the known shopper, in which case, commodity registration data is generated using the first and second commodity lists in combination.