Perhaps you have different collection and drop-off points, so how would that affect the cost of your car hire? Is it easy to search over a number of car hire firms or do you have to visit the web pages of each separately? How about searching over a range of countries? If you live in the USA and are traveling to Austria or Switzerland for some skiing, wouldn’t you like to be able to book the car you want and be able to get the best price for it?
These things are not easy to do and people generally settle for trying to get as near the head of the queue as possible at immigration and customs, and reach that car hire desk as quickly as they can. Then you have the problem of how many others have hired cars that day, and is the type of business car rental you need still available. It’s all worry and stress you can do without. What if you can’t get a car? It doesn’t bear thinking about! 3 kids and a wife, and you failed to get anything but a mini! That might be taking cheap car rental a step too far!