Roll your eyes all you want, but that whole "see something say something" attitude you probably grew up with is just a way to condition you to fear things you don't understand.

You need to get over yourself. No matter how bad you want to be a victim, no one cares enough about you to go after you. Those things you see as threats are city life. Yes a car idling for a long time is a bad idea, but were you hurt by it? Did it roll into you? Did the backpack bite you?

You are not going to prevent the next 9/11 by calling the cops on people who are just living their lives differently than you.