I fear that tips are going to be added onto the fare as a "fee" and not be adjustable except upwards. While I certainly am in favor of the staff getting the recommended tips from everyone, what I'm concerned about is once the fee is added then we will gradually become inclined to tip more as a matter of custom. Then we will be tipping the same amount despite the fact tips are now a fee attached to the ticket price.
Also, tipping is incentive based. If you want the server to give extra special service it is our custom to tip for this.