Hawthorne introduces so many of the townspeople on the way to the orgy or in attendance there because he wants to create the impression that everybody is secretly evil and in league with the Devil. They include the leading citizens, those who are noted for their piety and integrity and even instruct others in the observance of traditional religion. Young Goodman Brown and his wife Faith are novices. They are there as "converts" to be initiated into the established body of secret sinners and "fiend worshippers."
Young Goodman Brown is not necessarily as "good" a man as his name entails. His trip into the forest is never clarified, but he joins others in attending what might be a witch's coven, and although he renounces it, the fact remains that he went; his heart, which may have been flawed, becomes fully broken by the experience, but he did not seek to leave until his revelation.
Put yourself in Brown's shoes as he is shocked at how many people he sees on the same trail that he knows and has looked up to during his life. He went into the woods out of curiosity, but finds that there are so many other people whom he respected and loved. This is quite traumatizing to him to the point that he is bitter for the rest of his life. Each character that he meets from his own life drives his disappointment deeper, even though he himself is there! The devil will be evil no matter what; that's not a surprise, but finding people that you thought were better than that doing the same thing or worse is just dishearetening!
You might want to consider how characters help to identify the allegorical significance of the story. The names for example of the characters indicate the way in which their importance relates to the kind of concepts or qualities that they stand for. Faith is an obvious example, and it is key that it is when Goodman Brown (another important name) deserts Faith, literally leaving her behind, that he encounters the Devil and sees what he sees.
The Devil is an intriguing character in this story. You may want to ask yourself to what extent the devil is present as a tempter and to what extent Brown is responsible for his own problems. You may also want to ask yourself to what extent (if at all) the devil may only be a figment of Brown's own imagination. Finally, you may want to ask yourself in what ways Brown himself becomes a kinde of evil figure by the end of the story. The devil may only have been a dream, but Brown's malevolent behavior at the end of the tale seems all too real.
Faith and Young Goodman Brown are the key characters in the story, as it is the story of Brown's travels into the woods one night on a mysterious "mission" that changes, forever, his understanding of everyone around him. Brown's wife's name is Faith, and each time it is used in the story it is used as a pun on having religious faith. Brown leaves Faith and his faith at home one night as he heads out to a meeting with the devil who promises insight into the "secret heart of men." Brown is all but determined to turn away from the Devil when he sees what he perceives to be Faith's pink hair ribbons. Once he sees that even his sweet wife is a sinful follower of evil, he goes forward to give in, but at the last minute saves his soul and walks away. The problem is, even though he saves his soul, he is forever changed in his views of everyone else he thinks he saw at the witch's meeting that fateful evening. He ends up a bitter man.
Thank you all of you. I appreciate your comments.