Maybe they couldn't rent it back out right away? After all if you didn't need it why do you think someone else did? Companies aren't at 100% capacity all the time. Anyway why is it their responsibility to find a new renter when you had already agreed to keep the car for a week?
Apropos of the principle of this, most car rental companies these days are above capacity most, if not all the time.
You're lucky to get your car class. You're lucky if you don't have to wait around for it, or for it to be cleaned (last rental I had, "hasn't been returned yet and should have". There was no suggestion that they call the renter, and after about 20 minutes of being ignored, I said to call me when it came in. It came in 2 1/2 hours later.)
What's more, this is entirely of their own making, because most of those companies, or franchises or whatever, have decided to sell as much of their rental stock while they can make good profits. Only person it sucks for is you.
The OP's complaint was about an incident from 8 years ago. Regardless, it sounds like a lot of the problems you've experienced stems from renters who fail to honor their original contract or rental agreement -- returning cars hours or days late, or early, just like the OP. Not really sure what you want the rental company to do when cars aren't coming back to them according to schedule.
