Because each state has its own protocols, indeed, its own levels of EMS training (ie NY has EMT Basic, EMT Intermediate, and Paramedic while PA does not have the middle option) you won't find this c-collar rule to be the same everywhere. We are taught to carefully consider the mechanism of injury and and patient complaints before applying a collar. I recently assisted at a scene with a vehicle rollover, and when we arrived all four occupants of the rolled over van were standing there consoling each other. To look at the vehicle and the M of I you'd think it would be an immobilisation situation for sure, but based on what the patients were telling us they were not only not collared but they all boarded the ambulances under their own power and were just fine. Immobilising two of them would have been silly, and the other two just would have been upset by it; they were fourteen years old and already upset by having been in an accident. EMS actions in the US aren't only driven by fear of lawsuit; some of us do employ good training and common sense.