Paraprosdokian? Doesn't he own a diner in Astoria? Actually, turns out a paraprosdokian is defined as "a figure of speech in which the latter part of a sentence or phrase is surprising or unexpected in a way that causes the reader or listener to reframe or reinterpret the first part. It is frequently used for humorous or dramatic effect, sometimes producing an anticlimax."
Examples mentioned at Wikipedia:
"If I am reading this graph correctly — I'd be very surprised." —Stephen Colbert
"You can always count on the Americans to do the right thing—after they have tried everything else." —Winston Churchill
"If all the girls who attended the Yale prom were laid end to end, I wouldn't be a bit surprised." —Dorothy Parker
"I've had a perfectly wonderful evening, but this wasn't it." —Groucho Marx
More on paraprosdokians.