On a cold, blustery afternoon the week before Halloween, an assortment of spiritual mediums, animal communicators, and astrologists have set up tables in the concourse beneath the Empire State Plaza in Albany, New York. The cavernous hall of shops that connects the buildings in this 98-acre complex is a popular venue for autumnal events: Oktoberfest, the Maple Harvest Festival, and today’s “Mystic Fair.”