How late were you? If you showed up when you said you would, did they have a car waiting for you?

Though I agree with them, if you were going to be late you should have notified them though that doesn't mean they would have held a car if they had one available.

Given the choice of somebody at the counter to pick up a car, and somebody who may or may not be coming who is already late, they will give the car to the person at the counter.