If you saw a crime being committed, is it better to help or take photographs that could help in evidence? If there was an accident of some kind a photo of the scene could be of significant use before things get re-arranged by people helping? How much are you personally able to help realistically anyway in those kind of scenarios?
I'm sure that many people would be naturally averse to someone standing there taking pictures in such situations and I'm sure "ghoul" would soon be uttered but maybe sometimes it could actually be the best thing that you could do?
As a first responder, I can assure you that there is a time when it is best to pick up the camera.
Obviously, people come first in any considerations, but in many cases, once the properly trained/equipped people are on scene throwing additional people into the mix, even though they mean well, can be detrimental. There is a time to stand back and let the team work without you.
For example, I was first on the scene of a car accident. One car rolled and had two occupants, one with superficial cuts and the other with more serious bleeding. The driver of the other car appeared to be unhurt. I took control of the scene, had one person call 911 and wait for the ambulance, sent another back to the truck for the first aid kit, and got the bleeding under control while we waited for the ambulance. Fortunately, it looked a lot worse than it was and the police arrived in minutes and the ambulance a minute after that. At which point I was not needed anymore, surrendered the kid to the paramedics and started talking to the police.
While all this was going on, one of the onlookers came over and said that the guy from the other car got into another car and drove away and that she took pictures.... It seems he was driving without a licence and was drunk. Because of her picture they were picked up a few minutes later by another police car on the way to the scene... It went to court... her cell phone pictures convicted him.