Most of my car rental experiences are like that one Seinfeld episode. I reserve car X, and when I get there, they say they don't have car X (that they allowed me to reserve) but I can use car Y. Sometimes it doesn't matter at all, especially if they're going to pay for the gas. But it does bother me that I want a Honda Civic and walk out with a Dodge Charger or Ford F250.
I've run into this and it sucks. "all our cars are rented"
there are times when there are no cars.