The story was written mainly to show different meanings of

the same or similar phrases:

 

(1) behind bars: in prison.

 

(2) behind the bar: in the 4th stanza, meaning behind the bar counter 

 

(3) behind the bar: in the 7th stanza, meaning behind the bar restaurant.

 

(4) Monkey Bar: the name of a bar. There is an actual bar named like that on the 54tg street in NYC.

 

(5) monkey bar: a sport instrument on which people use their arms to move across.