It's just, who has the money. Some quite research shows that paul brakes are not quite worth their weight in gold, but they are close. If I had the money to spend on brakes that cost as much as my bike, maybe I would, I just feel that same money can go to better places. Especially given that they seem to solve problems I've never had (I've never had an issue with durability, never wore out a spring and never had trouble stopping on a dime with even the cheapest brakes out there).