"The directors of Lyft and Uber are legally required to maximize profit for the respective shareholders."

This is utterly not true, and even companies like Google have (had?) it specifically written into their shareholder prospectus that this wouldn't be the case. Companies which maximize profit at any cost are doing it because they want to not because they have to.

http://www.nytimes.com/roomfordebate/2015/04/16/what-are-cor...