Most don't consider it a career, though, and work these jobs to supplement their income. They'd likely be much better off mowing lawns.
That has not been my experience in Miami. The majority of the Uber/Lyft drivers I've met do it as their primary full time job. Miami may be unique though since there's such a high constant influx of low income/low skilled immigrants who find Uber/Lyft attractive since all you need is a car and a smartphone.
