Knowing Uber's reputation, I doubt that they would use the trip origin and destination as only input variables. I'm sure they know a lot about the user from their history, credit card, social media accounts, etc.

Why would Uber stop at the route and not charge by estimated user income, their job, age or maybe even the reason why they are traveling?

From what I read, I also understood it to be based on the route (start location and end location).