Elderly couple comes by around noon or so, and spend a lot of time looking at one of Rosemary Feit Covey's "Peep Show" boxes. I spend a lot of time talking to them.

These custom made boxes each has a set of 10 wood engravings which are inserted into the box and "peeped" through the keyhole. They are engravings of women in various state of being disrobed, objectified and enjoyed. Not exactly the genre of art that one would expect your stereotypical 80something couple to acquire for their collection.
They express interest and walk away to look at the rest of the fair. "They are major collectors," whispers the gallerist across the aisle from me.
A few hours later they return and buy the piece.
Only in New York.