I recently hired a car from Chambery and returned it the following week, having done maybe 400km (it was parked up most of the time). When I returned home to the UK later that day, I had an invoice from the hire company (Avis) for an additional 275 euros, for dropping the car off the day after I picked it up, in Strasbourg, having covered 1800km: the charge was made up of all sorts of things.
Their 'help desk' wasn't open until the Monday, by which time Chambery office was closed for the week. It took me several phone calls, tweets, emails etc to convince them that they had made an error and that the car was in fact where it was supposed to be. The final clincher that convinced the initially arrogant young French lady that they had made a mistake was when I respectfully pointed out that to have driven the distance I had in little over 24 hours, i would have had to drive solidly for the entire time at an average of 75kph.
On the damage above, I'm willing to bet that you weren't the first person to be charged for it. Nor will you be the last.
Daily driver: Jaguar iPace HSE
2000 NSX Coupe, Circuit Blue, was W2NSX now V6NSX
Renault Megane RS Trophy R
Other interesting mode of transport: Bell JetRanger