> In fact I don't even have to pay (the tip) if I don't want to. I still get a better driver, because they try to get me to tip.
You'll begin to get the reputation that you don't tip. Why would anyone pick you up then? You're essentially forced to tip if you want continued, good service.
> Well, that's easy to solve: don't allow drivers to rate passengers.
That's not a solution though; that's a hack to remove an undesirable affect from another feature (tipping). Just like drivers can be rated by passengers the inverse is also very important. These are still people's private cars after all; do you really want no way to rate the guy who trashes someone's car or is just an asshat?
You'll begin to get the reputation that you don't tip. Why would anyone pick you up then? You're essentially forced to tip if you want continued, good service.
> Well, that's easy to solve: don't allow drivers to rate passengers.
That's not a solution though; that's a hack to remove an undesirable affect from another feature (tipping). Just like drivers can be rated by passengers the inverse is also very important. These are still people's private cars after all; do you really want no way to rate the guy who trashes someone's car or is just an asshat?