Not Enough Petrol in returned Hired Car

I was surprised when I got my final invoice re document *** for Car Hire from Cape Town International Airport to see an additional charge to fill the car with 2,59 litres of petrol. I have filled up at the same service station for the last half dozen times using Budget Rent A Car and never had this added. Maybe you should supply your customers a list of service stations close enough to the airport so we can freewheel into the airport. I do not live in Cape Town so am not aware of the strategically placed service stations acceptable to Budget Rent A Car. I am annoyed and will certainly not bother to use your rental cars in the future. In the past 12 years I have used many different Car Hire companies out of Cape Town International and never had this happen with any of them. I think it is petty. (Maybe consider leaving a petrol can in the boot which customers can use to carry 2,59 extra litres to top up the car on arrival at the airport)