Those nearby market signals being extended by "the ether" is interesting, but a couple of years ago, as I drove northward toward Cols. thru Eastern Kentucky, I enjoyed hearing several stations from Quebec booming in on FM - listening to French pop music and commercials in the middle of hardscrabble coal country was a real treat. Those signals (I recall one was on 93.5, which is usually for lower powered local FMs in the US) stayed with me for at least an hour in the mid-afternoon.
Years ago (early 1970s), on probably two occasions, I recall the Geenie Antenna Rotor picking up TV signals from Florida at my home in Toledo, near Lake Erie. Too bad I was the only one in the family who found that more entertaining than what was actually on the local stations. Also, in the summer, the very powerful signal of channel 24 (we could easily see its tall mast from Point Place) often got a lot of lines in it, as the signal of channel 24 in Erie, Penna came in under it. That was my first lesson in how FCC frequency assignments don't seem to account for issues like ducting of signals across Lake Erie in the summer months. I wonder if the switch to digital TV signals has remedied that, or if they also experience interference from seasonal signal issues on the lake?