Uber's margin on a ride is already 35-40% in US cities (source: UberPeople), thanks to their 'upfront fares' pricing (rider fare is not used for calculation of driver fares at all, drivers are paid per mile/km and min), their Booking fees, UberPool pricing disparities, and Surge disparities (a rider paying a 1.5x surge does not necessarily mean a driver is receiving 1.5x).