A system for pumping gasoline includes a gasoline pumping assembly including a gasoline dispenser configured to perform a fueling process for a fueling process cost and a voucher assembly communicably coupled to the gasoline pumping assembly. The voucher assembly can include a coin receiver configured to receive a plurality of coins of a total value from a user and a voucher dispenser configured to provide to the user a remaining balance via a voucher when the total value is greater than the fueling process cost. The voucher can be a physical or digital voucher and can represent a value of the difference between the total value and the fueling process cost. The voucher can be redeemable for later fuel purchases or at related establishments.