What if they don't know what the sound of a Shotgun being racked sounds like?
Or they are tweakers who really don't hear, or care, about the racking of a shotgun. They are fixated on where they are going to get money/goods for their next fix because they are coming down.
No, I wouldn't just relay on the sound of the shotgun being chambered to scare the BG's/druggies away.
I mean, I guess that one could make that a part of their plan, hope that the sound causes the BG/druggie to run away and all is well but you have to have follow up plans, cause sometimes plan A just doesn't work.
Plan B, if you chose that as plan A should be the pulling of the trigger and then the sound of another shell being racked into the chamber. Plan C consists of repeating Plan B until Plan D can take affect, the calling of the lawyer.
Gangs are another problem in itself. Gang members believe that being shot, and then killing the shooter makes them better leaders, and it does give them a higher position in the ranks. And being shot and killed, makes them some sort of god that the other gang members then believe that they have to settle the matter, whether the person was just protecting themselves or not (law abiding), you killed their god (or if a low end, a brother/sister).
Believe it or not, even the bums around here have a "society" of brother/sisterhood going. I've found that I am on a "list" of the bum community because of how I dissed "one legged willy". It's also known by them that I am "protected" (long story, I've one foot in the "dark society" and one foot out. Thanks to my neighbor that died but he left word with his Brothers and he asked that my Uncle and I to be "protected". I will admit, this is strange to be able to view both sides of the fence).
Get a bum tweaked up enough, there is no telling how far they will go. Same with some of the Brotherhood that my neighbor belonged to. The sound of a shotgun will not even phaze them, unless it's the BOOM instead of the racking sound.