Offtopic, but perhaps illustrative: back when Hertz did very short term 'on demand' rentals the GPS system in the car was obviously faulty and I got a call from

Offtopic, but perhaps illustrative: back when Hertz did very short term 'on demand' rentals the GPS system in the car was obviously faulty and I got a call from someone from Hertz asking when I was going to return then rental, in a disagreeable tone. I told them I'd already returned it (usually locking the car at the return location terminates the rental). They didn't accept this and proceeded to tell me I should return it and the various consequences of not doing so. I told them again I'd returned it and suggested that their management unit was faulty which still didn't convince them. I then told them that there was a Hertz rental office right there and I'd put someone in the office on the phone who could confirm that I had indeed returned the car. They also rejected this. At that point I told them that if they wanted their car they could find it where I told them it was and that they should fix their system and there was nothing else I could do for them. She made some vague threat and I got off the phone. I never heard anything about it again and was billed correctly.