I had spoken with a state park employee that was responsible for a TIS. The area was VERY isolated and received NO radio signals. He stuck with the rules but had queried the FCC if they might point out needed services for travellers and if they might run some local announcements of interest to the rural ranching community. The impression he got from the FCC was running the National Weather Service was okay but otherwise the station was for talking about the state park. Mentioning business names or even acknowledging contributors was certainly not legal. In fact, it seems the Los Angeles Airport ran afoul with the FCC since their terminals were named for the airline that flew out from that terminal. With some convincing, LAX was allowed to use the airline names but that was a specific exception.
This TIS could have reallly been a service to the traveler because it was the only place where you had a convenience store and gas for almost 60 miles in each direction, but the FCC limited them to saying the community had limited travelers services since there was only one store, one gas station and only one auto repair/wrecker service. To mention them without business name would constitute a commercial since there was only one.
To run any programming other than the very specific and defined content would subject you to a fine. I personally think these rule are way too strict but I don't make the rules. Maybe Part 15 might be a better idea.