Uber is actually marketplace and it's goal is to balance demand and supply. Great upsides of being big company, e.g. having more cars and drivers, is 1) less waiting time for passenger and 2) less empty mileage for drivers/cars. First is good catch for client (I will not wait extra 10 minutes for Bobs Taxis even with 5% price difference), second is a no-brainer for drivers (one got paid for more hours ber day). Actually second one is a good edge against any local Bobs Taxis: with less idle time bigger company pays minimal wage faster and can make overall prices better.