Each full–service gasoline station offering self-service at a lesser cost shall require an attendant who is employed by the station to dispense gasoline from the self-service portion of the station to a motor vehicle properly displaying a distinguishing insignia placard or number plate issued to a person with a physical disability pursuant to section 28-2409 if the person to whom the placard or plate has been issued is the operator of the vehicle and the service is requested during those hours that full service is offered at that station.