Restaurants sometimes state that tables or parking or restrooms are “for eating customers only.” The joke is that this implies cannibalism of “eating customers” (rather than stating “customers who eat at the restaurant”).
   
“Parking for Eating Customers Only” was printed in the Arkansas Gazette (Little Rock, AR) on June 30, 1987. “Tables are reserved for eating customers only” was printed in the Montgomery (AL) Advertiser on February 23, 1995. “Bathroom is for eating customers only” was posted on Twitter by UNPRESIDENTED on May 18, 2013. “Restrooms are for eating customers only” was posted on Twitter by Some Professor on August 7, 2017.
   
     
30 June 1987, Arkansas Gazette (Little Rock, AR), “Arkansas Traveler” by Charles Allbright, pg. 1B, col. 5:
Then there is a sign on the parking lot at a Pine Bluff steak house:
 
“Parking for Eating Customers Only.” The question is, how much parking time is required for eating a customer?
     
Newspapers.com
23 February 1995, Montgomery (AL) Advertiser, “My Hometown” by Ragan Ingram, pg. 1B, col. 1:
Signs of the Times ... Rob Grant of Montgomery spotted this one at a convenience deli-store in Enterprise.
 
“Tables are reserved for eating customers only.”
 
Remind me not to be a customer at that deli, lest I fall into the clutches of cannibals,
 
Google Books
n and Out of English:
For Better, for Worse?
Edited by Gunilla M. Anderman and Margaret Rogers
Buffalo, NY: Multilingual Matters Ltd
2005
Pg. 136:
Another sign that is frequently seen in restaurant windows or displayed on doors is the inviting but ambiguous , even Neo-Chomskyan, For Eating Customers Only, presumably to dissuade the tourist crowd from only purchasing drinks.
 
Twitter
UNPRESIDENTED
@kierondwyer
A favorite Chinese restaurant sign of mine was in San Francisco and read, “Bathroom is for eating customers only”
1:22 AM · May 18, 2013·Twitter for iPhone
     
Twitter
MediaShow!ro
@mediashowro
Tables are for EATING CUSTOMERS Only http://mediashow.ro/429036
1:34 PM · Sep 29, 2014·Twitter for Websites
   
Twitter
Selena Templeton
@SelenaTempleton
Tables are for eating customers only. No loitering. So eat those customers quickly! http://fb.me/2L0W6YXfS
7:18 PM · Oct 1, 2014·Facebook
 
Newspapers.com
21 July 2015, The Morning Call (Allentown, PA), “Vulture carries two dead politicians on a plane…” by Bill White, News 10, col. 2:
One of my former colleagues sent me and others a restaurant sign that said, “TABLES ARE FOR EATING CUSTOMERS ONLY. NO LOITERING.” Cannibals welcome.
   
Twitter
Some Professor
@ProfessorSome
Replying to @DialUp56k and @Historiann
My personal favorite: “Restrooms are for eating customers only.”
4:48 PM · Aug 7, 2017·Twitter Web Client
   
Twitter
Lizzie Bruce
@CakeContent
Saw this in one of the Facebook pun groups (yep that’s plural) I’m in.
“Tables are for eating customers only. No loitering”
You need to be a speedy cannibal ok? Also maybe the tables are doing the eating so whoa, don’t hang about.
http://facebook.com/EnglishWhirledWide/posts/10157382706844295
#ContentDesignJokes Smiling face with open mouth and tightly-closed eyes
3:30 PM · Jun 3, 2019·Twitter Web Client
 
Facebook
Crazy World
Poster based in Spain · August 24, 2020 ·
RESTROOM IS FOR EATING CUSTOMERS ONLY!!!!