There is another reason: employment status and the resulting side-effects.
If you lock in a driver, you start to look like an employer with employees. This creates enormous payroll tax responsibility, workers comp insurance and other headaches for Uber/Lyft.
I would bet that Uber/Lyft have burned a metric crapton of lawyer and accountant brains in an effort to be on the "safe" side of the independent contractor vs employee fight. They're not going to screw that up.
If you lock in a driver, you start to look like an employer with employees. This creates enormous payroll tax responsibility, workers comp insurance and other headaches for Uber/Lyft.
I would bet that Uber/Lyft have burned a metric crapton of lawyer and accountant brains in an effort to be on the "safe" side of the independent contractor vs employee fight. They're not going to screw that up.