He's our protagonist, our title character, our central point of view, and a bit of an everyman. In fact, we can kind of relate to him. No, none of us at Shmoop have seen witches or almost joined a crazy devil cult. (Well, at least not yet.)
But most of us can relate to the struggles with temptation and pessimism that are at the heart of Hawthorne's story. This is why Hawthorne can spend pages and pages closely describing young Goodman Brown's thoughts and feelings without losing you. The story's events may be bizarre and unrealistic, but the emotions sure aren't.