Whole Foods charged $2.69 for a quart of "organic" skim milk in a paper container. If I could time a trip to New York State before my Saint Martin trip, Stewarts Shops sells milk in paper containers at normal prices.
Getting to JFK from my house is a big pain. Newark is better. but nothing is as convenient as PHL. We did, however, pay a premium for the Philadelphia non-stop SXM flight.