...in most parts of the country it is only available from local growers during the cooler weeks at either end of the growing season...
What country is this you speak of? AFAIK broccoli is on the shelves of my local stores pretty much all year. Sure, it's imported from somewhere insanely far away like China or Africa or Tierra del Fuego half the time, but it's there.
Not that I eat it, mind you. It's on the banned list, like Brussels sprouts. As Nicholas Freeling said about British peas, all I can suggest is that it be put into concrete barrels with radioactive waste and the Mafia, and sunk in the ocean.
"I regret to say that we of the FBI are powerless to act in cases of oral-genital intimacy, unless it has in some way obstructed inter-state commerce." -- J Edgar Hoover