Free Sirius?

Driving to the Metro in my pimped out Sienna this morning. Turned on the radio and tried to find that dope shit NPR plays, known around DC Metro as 88.5 FM. While sitting at a long red light near the house, the radio stops at 87.9 FM, and it's Howard Stern. At first, due to the low station number, I think it's a Charlie Rose-type interview with him. But no, it becomes clear that he's interviewing some retarded man about the size of his bowel movements. I figure someone must be trying to earn a buck by replaying his old shows. But then the f-bombs start flying (it turns out he's interviewing Bigfoot), and I mean, every third or fourth word was an expletive, unbeeped. It was clearly his satellite show. Then the light turned green, I started moving, and the station went to static. Couldn't pick it up again the rest of the short trip in. Did a car next to me at the light have Sirius, and the low station number was able to pick it up? Was the Methodist Church I was pulled up next to at the light an unwitting beacon for Howard Stern? Anyone ever hear of accidentally getting a satellite feed on your "Terrestrial" radio? Or is my Sienna just the best minivan a man could have?