I'm a driver but also a customer just as much these days. I always give a cash tip since i know that's the easiest way to a good customer rating. For some moral reason, I want to have a good customer rating. Anyway, I wouldn't show up as a good tipper under my actions. That's ok. I have found as a driver that those identified as top tippers do tip. And they are well behaved, etc. It's not worthless, but I wouln't necessarily take a bad ride because of it.