Why does the image of silence play an important role at this point in Of Mice and Men?

In Of Mice and Men, the image of silence plays a vital role in communicating the difficulty with emotional commitment during the time period.
The characters in Of Mice and Men struggle with poverty. The financial conditions that characters like George, Lennie, or Candy experience are trying. However, Steinbeck shows that poverty can also be emotional.  This emotional poverty prevents characters from supporting one another. Steinbeck shows emotional poverty is just as crippling as financial challenges.
Steinbeck illuminates this when he discusses "the silence" in chapter three. When Carlson proposes shooting Candy's dog, Steinbeck writes that Candy "searched the faces" of the men in the bunkhouse for support and was unable to find any. The emotional poverty of the men in the bunkhouse is reflected in how no one speaks out against the killing of Candy's companion.  Even Candy is afflicted with a type of emotional poverty in how he does not bid the dog farewell. He is unable to voice any emotion about someone so close leaving him.  
When Steinbeck writes of "the silence," it reflects the emotionally impoverished condition of the men in the bunkhouse.  The silence shows a reality where people fail to stand up for one another.  "The silence" is the sum total of their emotional commitment.  While the men do not like the silence that has permeated the bunkhouse, they do not say or do anything to show solidarity to Candy or his dog because of their emotional poverty.  Steinbeck uses the silence to communicate this condition.