“A guy walks into a bar…”  is a typical form of what has been called the “bar joke.” One version is:
 
“A man with authority walks into a bar. Order everyone a round (around).”
 
The joke was posted on Reddit on July 12, 2016.
 
   
reddit
A man with authority walks into a bar…
submitted July 12, 2016 by TapiocaTuesday
Orders everyone a round
(...)
COMMENYS
strikerdeath
For those who are a little slow:
a round
around
 
Twitter
litajtruong
‏@litajtruong75
A man with authority walks into a bar… Orders everyone a round #LMAO
2:53 PM - 12 Jul 2016
 
Twitter
MikaelaAna
‏@artemd6ye
A man with authority walks into a bar… Orders everyone a round #rofl
2:58 PM - 12 Jul 2016
 
Twitter
ShaniceMonica
‏@monica_shanice
A man with authority walks into a bar… Orders everyone a round #funny
3:14 PM - 12 Jul 2016
 
Twitter
BrownMurphy
‏@deniscdcershov1
A man with authority walks into a bar… Orders everyone a round #hahahah
4:42 PM - 12 Jul 2016