June, thank you for your note. I‘m inclined to agree with you that friendliness amongst strangers is a nice thing even when faked, especially when sharing a car. But, without sounding too much like a paranoiac I hope, I do worry about a system where both you and the driver are incentivised — by nothing greater than convenience — to behave like baristas. Being polite is a way of caring about others; I’m hostile to the way a rating system suborns it into just caring about oneself.