Uber is psychologically manipulating their drivers in order to exploit them. I know this because a New York Times article told me so. The article is titled, How Uber Uses Psychological Tricks to Push Its Drivers' Buttons, and starts, "The secretive ride-hailing giant Uber rarely discusses internal matters in public."
From this alone, I can deduce that Uber is run by tricksters who are manipulative of their employees and very guarded in their tactics for profit, which makes me assume they are unethical practices.
The New York Times piece does mention that Uber is trying to be more friendly and engaging with its drivers since they have gotten some bad press on that front. But the article goes on to inform me further of the exploitation:
And yet even as Uber talks up its determination to treat drivers more humanely, it is engaged in an extraordinary behind-the-scenes experiment in behavioral science to manipulate them in the service of its corporate growth…
Uber's innovations reflect the changing ways companies are managing workers amid the rise of the freelance-based "gig economy." Its drivers are officially independent business owners rather than traditional employees with set schedules. This allows Uber to minimize labor costs, but means it cannot compel drivers to show up at a specific place and time. And this lack of control can wreak havoc on a service whose goal is to seamlessly transport passengers whenever and wherever they want.