That's certainly one way to spin that. One would also argue that the situation went as best it could have. His friend was able to move freely with in a public place, conduct his business, and when the kids attempted to intimidate him/force their will on him, he was able to stop that from happening. He was able to do this without he or the kid being physically harmed.
I am curious if he reported this to the police. If he even did I doubt it was recorded in any meaningful way to allow us to see how many times a firearm in the hands of a responsible citizen is used to stop a violent crime. That's a statistic I would be interested in seeing.
I've heard speculation that it is a very high number.
Now one thing I will again agree on you with. Anyone on here that carries a gun for self protection. GET MORE TRAINING. In most cases your CCW instructor was a dickbag just wanting to make a buck. He/she didnt tell you all you need to know. Even if you had a good instructor 4 hours of range time isnt sufficient.
As GTO alluded to. People arent meant to kill other people (psychologically). Have you thought about what it would be like to actually have to kill someone? I know people who have had to do this. I knew them before and after, I promise you they were not the same.