Booking Couldn't Be Fulfilled After An Hour Waiting in Queue

I made an online booking for a car rental from Cape Town airport in February, but on arrival was faced with a huge queue outside of Hertz. The queue took more than an hour, during which time no manager came down the queue to apologise or explain anything. Finally we made it to the front of the queue but were then told there were no cars available and there would be at least another 45 minute wait. Since we could not wait that long due to other travel arrangements, we cancelled the booking. As a result, we had to make other travel arrangements for the weekend and were late for an existing engagement. To add to that, we wasted an hour in a queue for nothing, which affected other plans for the day. This was really shocking service - first to allow so many bookings without having guaranteed cars available, but secondly to have no management presence to explain or apologise for the situation and allow us to cancel the booking in the queue, which at least would have saved us an hour of waiting for nothing.