I sometimes hear PA announcements, just before the doors close, along the general lines of "If you don't want to be in Chicago three hours from now, this would be a really good time to deplane*." I've paraphrased this announcement several times in the first class of a semester. Every so often someone gets up sheepishly and leaves.
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*I dislike the made-up airline jargon word "deplane" intensely, but that's what they say.