Car Rentals, Still a Big Rip

If someone came in and introduced EDLP to a car rental business, they'd clean up. Aren't you sick of the price game, renting a car is like playing the stock market. For example, I recently booked a car with Thrifty, but then had to change my pick up date. I called them back and told them that I was willing to pay for my original quote, even though I'd be using the car for a few days less. They wouldn't hold the car for me if I couldn't pick it up on the same day and suggested that I re-book -- at 2 1/2 times the original price for a third less time.

Then I checked availability with Sunwing a discount carrier / vacation packager and actually found a car for that period for 1/3 the price (with Alamo) of Thrifty's. From a consumer's perspectice though, this doesn't make any sense...