As far as I know every Uber driver chooses to be one. Also, to be an Uber driver you have to own a relatively new car... I couldn't even drive for Uber because my car is too cheap. These people are not helpless.
To get a car loan you need employment history and decent credit. While some folks that fit this category are struggling, it's not exactly the profile of an exploited class.
Uber push their own financing program to recruit drivers (or to get drivers to update their cars). They use subprime lenders and claim that even people with poor credit are eligible https://get.uber.com/cl/financing/
