Uber has numerous requirements for THEIR drivers. They must maintain certain standards for the car, they must accept this many trips etc. You or I are obviously Uber's customers, and we pay Uber for a ride from A to B. We are not in any way John's or Jill's customers, they work for Uber to take us from A to B. Even if they can be classified as contractors, they are contracting for Uber, not for Uber's customers - that much is undeniable.