“What do you call a pig thief?”/“A ham-burglar.”

A riddle on the name of the “Hamburglar” (a character in McDonald’s restaurant commercials) is:
 
Q: What do you call a pig thief?
A: A ham-burglar.
 
The joke has been cited in print since at least 1993.
 
 
McDonald’s Wikia: Hamburglar
The Hamburglar is a McDonaldland character who features in McDonald’s commercials. He is a close friend of Ronald McDonald, Grimace, and Birdie. Even though he has always attempted (and failed) to hoard all the hamburgers in McDonaldland for himself, he has always been looked upon as a valued member of the McDonaldland community.
 
Hamburglar was voiced by Howard Morris in most commercials, Charlie Adler in some 1980s commercials and “The Wacky Adventures of Ronald McDonald”; and Carl W. Wolfe in some 1990s commercials. He was portrayed by Tommy Vicini from 1992-2003 after brief stints in the 1980s sharing the role with 20 year veteran Frankie Delfino (1971-1991).
         
14 November 1993, Palladium-Item (Richmond, IN), Stage 1 sec., pg. 1, col. 1:
Q: What do you call a pig thief?
A: A ham-burglar.
 
18 December 1996, The Sun (London, UK), pg. 5: 
What do you call a pig thief? A ham burglar!
 
Google Groups: rec.humor
Two dozen crackers
David Bridges
6/23/97
(...)
What do you call a pig thief?
A hamburglar.
 
Twitter
Charles Fenner‏
@ChasFenner
Q: What do you call a pig thief? A: A Ham-burglar.
5:59 PM - 27 Apr 2009
 
Google Books
The Ultimate Kid’s Joke Book
By Peter Coup
London, UK: Arcturus Publishing Limited
2013
Pg. ?:
What do you call a pig thief?
A hamburglar!
 
Google Books
Peppa Pig Jokes For Kids
By Jack Jokes
PeteyRF Creative
2016
Pg. ?:
What do you call a pig thief?
A hamburglar.
 
SORTEDfood
The 26 Worst Food Jokes You Have Ever Heard
26th March 2016
(...)
26. What do you call a pig thief?
A hamburglar