I discovered this by chance while driving in Columbus, OH, and rediscovered it the other day while driving in Ann Arbor, MI:
The frequencies used for VHF television channel 6 are:
CH BAND VIDEO CHROMA AUDIO
6 82- 88 83.25 86.8295 87.75
If you noticed, the audio is 87.75 MHz, and is modulated using Frequency Modulation. Guess what that means? If you are in an area of the country that can receive VHF Channel 6 on rabbit ears, then you can also listen to the programming on a FM radio, since the FM band starts at 87.7 MHz.
For Ann Arbor, I was receiving WLNS (CBS affiliate out of Lansing), while in Columbus, I was listening to WSYX (ABC affiliate).