Mega-rich people aren't investing in Uber in order to acquire power over serfs. They're doing it in order to make more money. So far, they seem to be mistaken in the potential profitability, but that doesn't make "feudal power over others" their goal.
Profitability may be a trifling concern for the companies, but it's not for the investors.
There's a lot of money in feudal power over others, once it's established, not to mention that it's an end-run around policy channels to reshape society. Some investors really do mostly want direct ROI and are likely disappointed by plays like Uber in this regard, but it's at this point kind of crazy to assume this is the main driving force behind such investments, given how often they cash out in power and policy change rather than direct profit
Profitability may be a trifling concern for the companies, but it's not for the investors.