It's certainly an important part of the service Uber offers, but that's rather the point, it's a service they offer to the passenger and contract others to do the work. Then the level of control is such that it makes the drivers workers in the UK. If the control was stronger (more control of hours, equipment, etc) then they'd be employees.

>However, I don't see how they can argue the driver has a contract with the passenger since all customer relationship is handled through Uber.

I fully agree, and I think we both do (at least on this point) with the employment tribunals findings that this doesn't really describe the reality of how things work. The description I referenced is a great attack on what they argue.