Bad neighbors are a whole other ball of wax, betty. Lol. I meant bad neighborhood.
Bad neighborhood etiquette has as many little rules as 'proper etiquette.' For example: You don't ask what people do for a living, but a little 30-second elevator speech about your values is instead the norm (not into bragging, gossip, game playing, loyalty, respect, courtesy, keeping it cool, etc.). There are only two paces to go at - a saunter and a dead run. If you see one of the scary denizens and start walking faster or cross the street - that's very offensive. You keep your head up but you don't take notice. If you do take notice, you have a compliment ready, 'cuz there's no other reason to be staring. If you catch someone's eye, pass close, you nod; mayhap exchange a little banter. You keep your eyes on your own test paper at all times.
There's more of course. But like now, living in a very very good neighborhood, everything is different. You cross the street so everyone can have a sidewalk to himself. You don't have to say hello at all when you pass, because we're all too important and busy for that. And at the same time, you expect to have your business poked into, to be quizzed about what you do.