Hertz Fuel Purchase Option Scam San Francisco California

 I guess Hertz employees are told to push the fuel purchase option at the car rental exit. This was the second trip in a row where the agent tried to talk me into taking the option by saying "you've got nothing to lose because if you fill it yourself, we will take off the fuel purchase charge". So I take the option and upon return find out I need to show my gas receipt. Nobody ever told me that. They can see the tank is full, but apparently that doesn't matter. So sent an email complaint and hear nothing. One week later, I call the billing department, but they want the gas receipt. How do they live with themselves for knowingly double charging customers for gas? Do they think anyone will actually rent from them again after experiencing this? At the very least, they should say we know you filled at least 95% of the tank, so if you have no receipt, we will charge you for 5% of the tank.