Being a jerk can have many faces and there are a lot of people right on the edge of getting in trouble but not quite. Those are also the worst people to work with IRL. They fall up the ladder and are usually pretty incompetent.
If they are repeat offenders, I confront them in the places I mod since I dont want them hollowing out the community by this constant low key abrasion.
Others who just have a hot temper I leave mostly alone until they really go overboard.
Thats how I do it and thats what I think is best. Obviously not everyones opinion though.