You made my point in your last paragraph.
I am not sure what that point is, but I am glad that my experiences square with your view of the world. My experience is that pot has been a contributing factor in violent crime on many occasions. Without the pot however, many of the crimes likely would not have been committed in the first place.
Pot, alcohol and other mind altering substance cause people to do stupid things that they probably would not do without them. Repeated and habitual use especially, appears to cause long lasting psychological damage.