Overhearing Jokes

A friend of ours sat down next to another passenger on a train recently and couldn't help overhearing his conversation out the window with a man standing on the station platform.
"Thanks for putting me up while I was here, Sam," said the passen­ger.
"Glad to do it," said the other man.
"Thanks for the food and the drinks-everything was wonderful."
"It was a pleasure," said the man.
"And thank your wife, Sam-she was great," said the passenger, as the train began pulling out. "I really enjoyed sleeping with her."
Our friend was rather taken aback by this exchange and he turned to his fellow passenger and said: "Pardon me sir, but I couldn't help overhearing your conversation. Did I understand you to say that you enjoyed sleeping with your friend's wife?"
"Well," said the fellow passenger, "I didn't realty enjoy it. But Sam is a hell of a nice guy."