I have been on the receiving end of exploitative business models. The answer is Exit, not Voice. Here's why: enough people exit -> wages go up and/or working conditions improve. Period. Yes, it's that simple. The problem is that we are creatures of habit, driving around is a relatively easy job, and the self-awareness necessary to change is scarce.
But wait, survival of the fittest and I don't give a shit. I really don't. These taxi/uber drivers will be replaced by driverless cars. We need a government program to retrain these people and employ them, just like we had for farmers and factory workers. Or not. Seeing people try to fend for themselves is more interesting than seeing them do make-work in a federal building - who knows, they might actually adapt, thrive, and makes something of themselves.