What is surprising about the A Hester has sewn for herself? What might this indicate?

In Chapter Two, we are introduced to the scarlet A which has become eponymous with the novel itself. Its introduction carries a touch of humor or, at least, resistance: Hester has appropriated the supposed symbol of shame as a beautifully embroidered letter, which she wears without the slightest air of anguish or despair. Indeed, the fine stitch work around the A has reduced it to an ornament, a decorative and trivial accessory.