Good question. Hey, why is there a big pear outside any store?
But for this big green pear, the key thing to remember is the store used to be a Grand Union supermarket. The chain was renovated in 1982, and this Yorkville store was the first to get a redo. The big Bartlett (it is a Bartlett) was meant to be the new trademark of the enhanced Grand Union stores.
However, Gristede's bought the building in 1988. It kept the pear for some reason (public outcry?), but moved it from its proud place on the sidewalk to a corner by the air conditioner, a ladder and some garbage. It's also bee defaced by graffiti. Folks just don't respect outsized fruit the way they used to.