“Waiter, this soup tastes funny!”/“Then why aren’t you laughing?”

A classic restaurant joke is:
 
CUSTOMER: Waiter, this soup tastes funny.
WAITER: Then why aren’t you laughing?
 
The joke was cited in 1931, when it involved the stew served in military barracks. The restaurant joke was printed in Boys’ Life magazine in April 1971.
 
     
17 April 1931, Olean (NY) Evening Times, second sec., pg. 8, col. :
NO LAUGHING MATTER
It was dinner time at the barracks.
 
“Any complaints?” shouted the orderly.
 
“The stew’s funny,” complained one man.
 
“Funny?” queried the officer. “Then why aren’t you laughing?”—Tit-Bits.
 
Google Books
April 1971, Boys’ Life, “Think and Grin,” pg. 74, col. 2:
Customer: Waitress, this soup tastes funny!
Waitress: Then why aren’t you laughing?—Mark Binkowski, Wausau, Wis.
 
28 September 1973, Long Beach (CA) Independent, “Stepping Out” by Tedd Thomey, pg. A-27, col. 1:
In another cartoon, an uppity waiter is questioning a patron who has a sour expression because he just ate something unpleasant. The waiter asks tartly: “But if it tastes funny why aren’t you laughing?”
     
Google Books
The Gigantic Joke Book
By Joseph Rosenbloom
Illustrations by Joyce Behr
New York, NY: Sterling Publishing Company, Inc.
1978
Pg. 193:
Customer: Waiter, this soup tastes funny.
Waiter: Then why aren’t you laughing?
 
10 May 1981, Newsday (Long Island, NY), “Smiles,” Kidsday, pg. K9, col. 3:
Boy: I’ll have the soup, waiter.
Waiter: Here it is.
Boy: This soup tastes funny.
Waiter: Then why aren’t you laughing?
—Victoria Chew, North Massapequa
 
25 April 1988, The Times (Trenton, NJ), Frank Tyger column, pg. A2, col. 1:
Customer: “Waiter, this soup tastes funny.”
Waiter: “Then why aren’t you laughing?”
 
Twitter
Jayadrathsingh‏
@jayadrathsingh
CUSTOMER- Waiter, this soup tastes funny.
WAITER- Funny? but then why aren’t you laughing?
3:31 AM - 24 Apr 2007
     
Google Books
Ultimate Book of Jokes:
The Essential Collection of More Than 1,500 Jokes
By Scott McNeely
San Francisco, CA: Chronicle Books
2011
Pg. 155:
Waiter, waiter! This soup tastes funny.
Then why aren’t you laughing?
 
Google Books
Food Jokes For Kids
By Peter Crumpton
PeteyRF Creative
2015
Pg. ?:
Waiter, this food tastes kind of funny?
Then why aren’t you laughing!??