I don't know where you live; it must be a wonderful place with lots of police and few nuts and criminals. I spent 25 years working with the police on a daily basis.
There are many times that a good citizen with a gun has saved the life of innocent people including themselves. It has nothing to do with a good citizen “playing cop”. Where we live cops are outnumbered by hundreds if not thousands to one. We often have just a few cops covering a huge part of the county. Depending on the situation it can be hours before they show up. Thank God for good citizens who are armed and willing to protect themselves and other good citizens. They are a major deterrent to crime in our area.
The gun club I belong to has the police range right next to it. We are behind two locked gates. The one we used is suppose to be closed after certain hours. The sheriff's department normally uses the other gate. I came in one time and locked our gate behind me. I didn't realize that the deputies were using our gate for some reason and none of them had the key to either.
After I finished my shooting and I went to leave, I found that there were a dozen deputies lined up in their cars waiting to leave. One of them told me that I had locked literally half the deputies on duty at that time in our part of the county in the shooting range. They were trying to find some bolt cutters when I unlocked the gate for them.
Yes we do have a lot of cops around here. It keeps the crime rate down.
I just arrived home a few minutes ago from my local watering hole and I calmed down a situation between an on again off again boyfriend of my neighbor's daughter. He and his 2 friends left quietly. It did help the situation that I was able to get the two friends on my side. And I wasn't wearing a weapon.