What DOES THIS MEAN?!?!

[Whippersnapper]

*Disclaimer, this was also posted in the Broadway chat board*

HELLO EVERYONE, 

I was cast as Banjo in The Man Who Came to Dinner. It has been very fun studying this character, especially once I learned from my director that he is based off of Harpo Marx. 

I've been doing some research on the plethora of 1930s references, and there is one Banjo line that is bugging me. 

The line is "Come to my room in half an hour, and bring some rye bread" 

Is there any reason for this line other than it re-affirms that Banjo is insane? Is there a reason rye bread is chosen? 

It's a disturbingly funny and odd line and maybe there's nothing more to it, but any insight from y'all is appreciated!