The Missing Tip

Chen is in America. His American friend, Daisy, suggested having lunch with him at a restaurant. (C=Chen; D=Daisy)
C : Why's that waiter so angry?
D : Those people who just left didn't seem to give him any tip, which made him angry.
C : Is that absolutely necessary here?
D : Kind of. It's the custom. You can't really avoid leaving at least a small tip.
C : But suppose the service is bad?
D : In that case, of course, we don't leave one.
C : And does the waiter know that's why you didn't give him a tip?
D : Exactly. It's just like telling him off.
C : No wonder he's so angry.
D : Well, in fact, the people did leave him a tip, but that kid over there took it.

黛西:那些刚走的人似乎没给他小费, 这令他不悦。
黛西:多多少少。给小费是个习惯, 你免不了至少要留一点小费。
黛西:那样子的话, 我们就当然不留。
黛西:正是, 那就像是在责备他。
黛西:嗯, 其实那些人确实给他留了小费, 但是那边那个小鬼把它拿走了。