A payment processing system and method comprising a POS module providing an interface to effect sales of FGS in a retail environment, a device module operatively connected to at least one retail device configured to supply FGS and comprising a card reader adapted to receive a first payment card data for payment for the FGS, wherein the device module is adapted to control operation of the at least one retail device, and a payment system module operatively connected to the POS module and the device module, the payment system module adapted to validate payment for the FGS. The payment system module and the device module are separated from the POS module in order to segment a portion of the payment processing system configured to handle payment card data from a portion of the system that does not handle payment card data.