The story also focuses on human loneliness and the need to bond with others.

The Rattrap deals with the issues of human loneliness and the need to bond with others. Not only the peddler but also other characters like the crofter, the ironmaster and Edla emphasise this fact.  

The peddler's conscience had left him because he had been lonely in his predicament, for a long time. But Edla's kindness and hospitality changed him. The crofter, on the other hand, is a lonely fellow whose craving for company leads him to give shelter to a vagabond, and he ends up getting robbed. Even, the ironmaster and his daughter suffer from loneliness. They crave company on Christmas Eve and are excited when they get the opportunity to serve a guest.

There are at least three characters in the story who suffer from loneliness and express the need to bond with others. They represent three strata of the human society as well. The peddler with the rattraps, the old crofter and the ironmaster all suffer from loneliness. The peddler is called a tramp, a vagabond and stranger at various points of the story. He moves wearily from one place to the other. He is lost in his own thoughts. He seeks shelter for night and people look at him with sour faces. Ev en the blacksmiths look haughtily at him and nod consent. The old crofter suffers from loneliness as he has neither wife nor child with him. Hence, he feels happy when he gets the peddler to talk to in his loneliness. 

The ironmaster is also lonely in his manor house. His wife Elizabeth has died and his sons are abroad. There is no one at home except his oldest daughter and himself. His requests to Captain v on Stehle to accompany him show his need for human bonding. He admits frankly that they didn’t have any company for Christmas. The stranger turns down the request not because he is against bonding with others but because he fears being caught with stolen money.