A skeleton riddle was posted on the newsgroup alt.humor on September 29, 2000:
Q: Why didn’t the skeleton eat the cafeteria food?
A: Because he didn’t have the stomach for it!
A similar skeleton riddle (about Halloween candy) has been cited in print since at least 2012:
Q: Why didn’t the skeleton like the Halloween candy?
A: He didn’t have the stomach for it.
Google Groups: alt.humor
Looking for halloween material
fmhlaw
9/29/00
(...)
Why didn’t the skeleton eat the cafeteria food?
Because he didn’t have the stomach for it!
Google Groups: alt.humor.puns
“Puns of the Weak” 10/20/00
Stan Kegel
10/21/00
(...)
Why didn’t the skeleton attend the banquet? He didn’t have the stomach for it (By Gary Hallock)
Google Books
Spooky Sillies:
A Book of Ghost Jokes
By Mark Moore
Minneapolis, MN: Picture Window Books
2005
Pg. 7:
Why didn’t the skeleton eat the cafeteria food?
Because he didn’t have the stomach for it.
Google Books
December 2012, Boys’ Life, “Think & Grin,” pg. 63, col. 3:
John: Why didn’t the skeleton like the Halloween candy?
Mark: Why?
John: He didn’t have the stomach for it!
John Capelli, Houston, Texas
Twitter
insanescouter
@insanescouter
#ScoutHumor John: Why didn’t the skeleton like the Halloween candy? Mark: Why? John: He didn’t have the stomach for it!
4:10 PM - 23 Feb 2016
Twitter
ScoutBot
@ScoutBot
#ScoutHumor John: Why didn’t the skeleton like the Halloween candy? Mark: Why? John: He didn’t have the stomach for it!
4:15 PM - 23 Feb 2016
Twitter
JDL-evision
@JasonDLouie
@kararoyster Did you hear about the skeleton who turned down all of the candy he was offered?
Turns out he didn’t have the stomach for it.
5:06 PM - 10 Oct 2017
Twitter
tess cook
@Tessbc7
why couldn’t the skeleton eat any halloween candy??
He didn’t have the stomach for it
11:03 AM - 14 Oct 2017
Twitter
BRITÁNICO
@elbritanico
#Joke
Q: Why didn’t the skeleton like the Halloween candy?
A: He didn’t have the stomach for it!
11:48 AM - 17 Oct 2017