This is wrong on numerous levels. For starters, such a service would be materially inferior to what Uber is providing. The payment mechanism is almost irrelevan

This is wrong on numerous levels. For starters, such a service would be materially inferior to what Uber is providing. The payment mechanism is almost irrelevant. What you describe would not be any more legal nor much harder to police. And you drastically overstate the commodity nature of the service (in fact, it's a winner take most/all scenario).