In "The Minister's Black Veil: A Parable," why do the parishioners have such an intense response to seeing the minister's veil?

Mr. Hooper's
parishioners have an intense reaction to his black veil, at first, because it is extremely
off-putting.  They are very confused by it because it is so uncommon a thing for a person to
cover up their face in this way; we especially like to see the eyes of any person to whom we
speak.  They first wonder if it is even their minister behind the veil, and then one old woman
says that "'He has changed himself into something awful, only by hiding his face," and
another man cries, "'Our parson has gone...