Ride sharing and rental companies are competing for profit as well, and ultimately they'll bring costs to be as expensive as they can until turning people into switching to the status quo alternatives.
Similarly people thought ebooks would be significantly cheaper, however counterintuitively they're not much cheaper and sometimes more expensive than a physical book because digital books are more convenient for many people.
A book author has basically 100% market monopoly on his/her books. He can set a high price and people who want to read the works will still pay.
Whereas ride sharing companies interchangeable and are in full competition with each other, which, in a healthy market, should bring the price down to the point where they're all only making a marginal profit. The cost of alternative mode of transportation does not come into equation (well unless it's overall cheaper and better - then it will kill the entire market segment).
Similarly people thought ebooks would be significantly cheaper, however counterintuitively they're not much cheaper and sometimes more expensive than a physical book because digital books are more convenient for many people.