I snapped this picture at my local Food Emporium, which is a very normal, smallish Manhattan grocery store.
In the foreground you can see packs of ping pong balls. Now, according to this valuation map (http://www.curbed.com/archives/2006/03/08/salmon_bites_valuation_map_of_manhattan.php) Ping pong tables are prohibatively wasteful uses of space. So it took me a few minutes to figure out why a store that virtually no other non-food products stocked them.
Aha, the answer: Beer Pong.