Hidden charges such as Flex Fuel and Additional Driver

The GOLDCAR representative insisted that we were required to pay an additional charge for "Additional Driver" and "Flex Fuel" even though our Easyrentcars.com reservation said that we would owe $0.00 upon vehicle pickup. When we asked why we were required to pay this, the GOLDCAR rep told us that is how the reservation came through even though he couldn't show us on the paper.