Interviewer: "Are there any rules of thumb that you can use to determine if someone is going to be a good tipper?"
Informant: "No, you'd be surprised. Its something that we talk about at the restaurant occasionally. That you can't ever peg a customer. And you really shouldn't try to because you'd be surprised in the end who's going to tip and who isn't. And sometimes by stereotyping or pegging, you end up getting the kind of tip you expected because subconsciously or consciously you end up giving worse service because you expected it.