Jack in the Box fast food restaurants are located primarily in the West and in the South; there are over 900 restaurants in California and over 600 restaurants in Texas. The company began in 1951 in Long Beach, California, and features a clown spokesman named Jack.
 
The nickname “Gag in the Bag” (or “Gag in a Bag”) for Jack in the Box has been cited in print since at least 1990 and is still popularly used. Jack in the Box has also been nicknamed “Jack in the Crack” (cited in print since at least 1991).
   
   
Wikipedia: Jack in the Box
Jack in the Box (NASDAQ: JACK) is an American fast-food restaurant founded by Robert O. Peterson in 1951 in San Diego, California, where it is still headquartered today. In total, the chain has 2,200 locations, primarily serving the West Coast of the United States. California is the state with the greatest number of outlets (927), followed by Texas (611), Arizona (177), Washington (143), Nevada (77), and the bi-state St. Louis metropolitan area (72, between Missouri and Illinois). Since 2000, the company has also opened outlets in North Carolina and other Southern states. The company also operates the Qdoba Mexican Grill chain.
       
Urban Dictionary 
Gag in a Bag
It’s the real moniker of the somehow popular restaruant “Jack in the Box”, derived from the sickening feeling you get after eating their ground horse ass.
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by ganjboy420yaa Sep 10, 2008
     
Google Groups: rec.humor
Newsgroups: rec.humor
From: .(JavaScript must be enabled to view this email address) (Dan Hinojosa (Guest))
Date: 8 Oct 90 20:21:31 GMT
Local: Mon, Oct 8 1990 3:21 pm
Subject: Re: Foodonyms
 
For Jack in the box, we used;
gag in the bag
   
Google Groups: rec.humor
Newsgroups: rec.humor
From: .(JavaScript must be enabled to view this email address) (Marisa SorBello)
Date: 3 Jul 91 16:47:42 GMT
Local: Wed, Jul 3 1991 11:47 am
Subject: Re: American food
 
I always liked Gag in the Bag (for Jack in the Box)
 
Google Books
The Body Shop:
Parties, Pills, and Pumping Iron - Or, My Life in the Age of Muscle
By Paul Solotaroff
New York, NY: Little, Brown, and Co.
2010
Pg. ?:
“Let’s do a Jack in the Box run.”
The younger girl giggled and bounced on her toes. “Yay, we’re going to Gag in the Bag!”
 
List Of The Day
Monday, July 12, 2010
Store Nicknames Of The Day
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JACK IN THE BOX
Yack In A Box
Jack In My Box
Jack In The Crack
Gag In The Bag
 
Ask MetaFilter
Nickname that store
November 30, 2010 8:53 AM
(...)
Jack in the Box = Gag in the Bag or Hack in the Sack
posted by expialidocious at 11:49 AM on November 30, 2010