Ah, this explains an experience I had recently. Just the other Saturday I was walking down Amsterdam Avenue, and I could see from a few blocks away that there was a garbage truck on its rounds through the neighborhood. It seems that it was a particularly heavy garbage day, and the two sanitation workers in charge of the truck were having quite a time trying to handle the volume. In fact, they had just run out of room, and were stuffing trash in any way they could. Finally, it was so overflowing that one of them had to climb on and stretch himself across the back, literally holding in the garbage with his body.
As I passed a synagogue on Amsterdam Ave, some congregants were standing in front after services, and two old ladies watched this truck barreling past them. One of them turned to the other and said, "Would you believe it? Somebody threw out a perfectly good Shabbos goy!"
It all makes sense now. Thanks for providing the cultural background.