Literally the opposite of a hundred years of research. Consider this - I'm 65 and do Uber part time because I'm bored. Now I'm 20 on a student visa with a work

Literally the opposite of a hundred years of research. Consider this - I'm 65 and do Uber part time because I'm bored. Now I'm 20 on a student visa with a work limit, and not many ways to support myself. Who should get the next Uber trip? Should Uber flip a coin? Must we be paid the same? If the student is willing to work for less than what the senior would get out of bed for, why would a free market not allow this? How do these dynamics affect the prices that customers pay?