Except for saving human lives in emergency situations. I doubt the self-flying plane would land in the Hudson river and saved all the passengers.
There's nothing 'simple' about landing an airplane in water that is not designed for it, especially a glider.
Most computer guys don't realize this, but you can't save the state of a flight. Most decisions are mostly permanent once made. And some, like for instance all decisions made on an aircraft with no engines, are completely irreversible. So if you don't make the right choice on the first try, you have to live with the wrong choice. At low altitudes under visual flight, a pilot makes multiple such decisions a minute. In an emergency, this number would be a lot higher; on the order of once every few seconds.