“What is cardboard’s favorite sport?”/“Boxing.”

The sport of “boxing” doesn’t have anything to do with cardboard boxes, but there are jokes. A cardboard riddle has been cited in print since at least 2016:
   
Q: What is cardboard’s favorite sport?
A: Boxing.
   
     
Twitter 
🌸✨
@heizeing
whats a cardboard’s favorite sport?
boxing 😊
10:50 AM · Sep 14, 2016·Twitter for Android
     
Reddit—Jokes
Posted by u/sketchbreaker October 5, 2017
What is cardboard’s favorite sport?
Boxing
 
Twitter
me
@not_actuallyme
What is cardboard’s favorite sport? via /r/Jokes http://ift.tt/2yKeIRm
12:43 PM · Oct 5, 2017·IFTTT
 
Reddit—Jokes     
Posted by u/raykendo August 11, 2019
What is cardboard’s favorite sport?
Boxing
-brought to you by my 8-year-old son
 
Reddit—Dadjokes
Posted by u/AJ-Naka-Zayn-Owens September 24, 2019
What is a cardboard’s favourite sport?
Boxing
 
Twitter
Dave Goulden
@davemgoulden
What’s a cardboard’s favourite sport?
....Boxing
Admit it, you laughed
12:31 PM · Sep 29, 2019·Twitter for Android
 
LaffGaff
By laffgaff December 24, 2019
Favorite Sport Joke
What is cardboard’s favorite sport?
Boxing.