Their in-force presence keeps a lid on any immediate retaliatory acts, as well as the monkey-see/monkey-do culture of violence.
Especially during those warm Summer nights with people hanging out on porch steps, perhaps fortified with a bottle or three of Champipple, Stripple, and a Thunderbird Shake'em Up.
This all very logical. The weather here in Illinois has been unseasonably warm so the nitwits get out from in front of their TVs and do what they do best...shoot each other.
No mystery here.
Bing Bing Bing! We have a winner.