A Senator from New York says to his friend, the Wyoming lawyer, that he has a perfect way of eating for free in restaurants. "I go in at well past 9.00 PM in the evening, eat several courses slowly, linger over coffee, port and a cigar. Come 2.00 AM, as they are clearing everything away, I just keep sitting there until eventually a waiter comes up and asks me to pay.
Then I say: 'I've already paid your colleague who has left.' Because I am a politician, they take my word for it, and I leave."
The lawyer is impressed, and says: "Let's try it together this evening."
So the Senator books them into a restaurant and come 2.00 AM they are both still quietly sitting there after a very full meal. Sure enough, a waiter comes over and asks them to pay. The Senator just says: "I've already paid your colleague who has left."
And then the lawyer adds: "And we are still waiting for the change!"