I've had run-ins with "gang bangers" before, but I don't let that affect the way I see them because we're all human. As long as you don't do anything to challenge their manhood (in some cases, "womanhood" because female gang members can take shit serious, too) or color/gang, you're okay. But sometimes they do get out of hand and fuck with random people, so be alert.
And yeah... arguing over "why you got so much blue/red on?," "where you from?," "what tou claim?," "what you looking at, puto?," or "what's so funny?" is childish and can bring back 1st grade flashbacks. Just remember that the person asking such question feels the need to let whatever's bugging them (or peer pressuring them) take it out on you.