Creating and maintaining software that connects a person with a device to a driver with a device and routes them from point A (driver) => A' (person) => B (destination) isn't some trivial nothing that you can just rent-seek into existence. I believe 'wealth' was added to the economy that did not previously exist when people had to deal with hailing cab drivers, not have a map of their route, and not know an approximation of their fare ahead of time.