What suggests that the speaker of the poem "Richard Cory" is speaking for the entire town?

In the poem "Richard Cory," the speaker indicates his/her position as representative of the citizens of the town with the repeated use of the pronoun "we." This pronoun aligns the speaker with the others who are poor, both in their economic plight and in their sentiments.

Initially using the expression "we people on the pavement," the speaker represents the citizens who suffer during the hard times of the depression of 1893, in which people could...

In the poem "Richard Cory," the speaker indicates his/her position as representative of the citizens of the town with the repeated use of the pronoun "we." This pronoun aligns the speaker with the others who are poor, both in their economic plight and in their sentiments.

Initially using the expression "we people on the pavement," the speaker represents the citizens who suffer during the hard times of the depression of 1893, in which people could not afford to purchase meat and subsisted mainly on bread that was often a day old. Thus, the disparity between the citizens of the town and Richard Cory, who is "richer than a king" is marked. Further in the verses, the contrast between Cory who "glittered when he walked" and the people becomes even more defined. And, each time this contrast is mentioned, the speaker is aligned with the townspeople as always "we/us" heads the description of feelings: "we thought...," "to make us wish...,""we worked and waited for the light," and so forth. 

Along with the other citizens, too, the speaker never inquires as to why Richard Cory has come to town, and why he is "always human" when he speaks to them. Instead, this speaker and the others feel that the only misery is in their condition, failing to understand that a rich gentleman can also suffer misery, albeit a different kind.