Most of those you mention use satellite radio, not stations that have to be changed when the signal fades out within an hour of driving.There are plenty of drivers on the road overnight who could very well be glued to their radios. Amazon, UPS, FedEx, USPS, long-haul transport drivers, and regular people like me who choose to drive at night.
Keep in mind that one of the big reasons to run 24 hours a day is to not have the big surprise of a transmitter that won't turn on at 6 AM. When I owned stations, I got tired of losing an hour or more in AM drive when something did not turn on and decided to make every station I owned run 24/7.So there is an audience for breaking news on talk radio stations, but again the main audience for this story is radio station executives who see the trade publication headlines like the one linked in the first post, and take that into consideration at contract renewal time.