There are eight Tesla superchargers at Woodman's grocery in North Aurora IL. If there is a J1772 there, would it be an extra hose on one of the chargers? I haven't really examined them closely because I was so steamed to see so many Tesla chargers and nothing for me...
"Superchargers" are Tesla specific high speed (typically 120 kW or more) DC chargers, and not your typical J1772. So not compatible with the Volt in any way.
"Destination chargers" are lower power (20 kW or less) AC charging stations at hotels, motels, and other points of interest. They are J1772 in electrical protocol, but have the Tesla specific plug on the end. One could actually hack off the plug and use a J1772 plug, and it would work fine with a Volt. In fact one outfit is in the process of making adapters available so J1772 cars can use Destination chargers.
Have only seen one Tesla charging there, one time. Most of the time all are empty. No one at the store knows anything about this, so there's no one to ask.
Partly because Superchargers charge the cars so fast, they don't need to hang around for very long. But, I suspect, also partly because the Supercharging network hasn't supported travel westward across Iowa - until the very recent installs in the QC (Davenport), Iowa City, and Des Moines. With these latter Superchargers in place, I think Aurora will start to see a lot more use.