In his autobiography, Charles Chaplin described the making of this film as "like pulling teeth" due to the mental block he suffered as a result of his unhappy marriage to Mildred Harris.
When the Farm Handyman (Charles Chaplin) drops the egg shell into the coffee pot, he is not simply surreptitiously disposing of the shell. Egg shells, being alkaline, decrease the bitterness of the coffee. This was a common practice for the time.
Butter costs $.22/lb at the store; this corresponds to about $3.50/lb in 2021, which is about the actual price.
The doctor's (vet's) bill of $10 that the Slicker paid would be equivalent to over $150 in 2021.
Anne Sullivan and Helen Keller visited the Chaplin Studio on LaBrea Avenue in Hollywood while Chaplin was at work on this film. Keller and Sullivan were photographed on still-standing sets from Shoulder Arms (1918) communicating with Chaplin.