A gas station cashier is a customer service representative and store clerk. As a gas station cashier, your duties include greeting and assisting customers, maintaining the inventory of products on store shelves, operating the cash register and running credit card transactions, and cleaning the gas station shop and restrooms. You may need to do some heavy lifting when restocking store shelves with items from the storage room. If you work at a 24-hour gas station, then you may have to work occasional overnight shifts.