Priceline.com review: Wouldn't refund even when car rental company didn't have any cars

Thrifty car rental Maui had only a few agents for hundreds of rentals. took two hours to get a rental agreement, went to the garage and there are no cars and all those people who were in line are now in line waiting for cars. dozens and dozens of people ahead of me and 4 cars delivered in the next hour. Was told it would be at least another hour for a car. Contacted priceline and they wouldn't cancel my reservation since I had a no cancel/no mod reservation. Got another car anyway from another company in 5 minutes. the delay cost me a long panned hike into Haleakala with my daughter because we couldn't get to the wilderness camp in time since we lost three hours of daylight forcing me to find last minute accomodations. Priceline is standing by their no cancelation policy even though the vendor couldn't provide me a car and no one at priceline would tell me how long would I have to wait until they consider the reservation unfulfilled. 4 hours? the next day? eventually there is a failure to provide service, but priceline still thinks they get to keep my money.