While I have no problem with "profiling," including profiling which has race as a major factor (but certainly not a sole factor), I would like to point out that just because some Black adolescents (or "Hispanic," if that fits the stereotype in your neighborhood) are dressed like young criminals, it does not necessarily mean that they ARE young criminals. Sometimes fashions of dress among high-school kids follow the criminal element even though the behavior doesn't. Where I live, far more high-school kids wear ill-fitting jailbird clothing than could possibly be criminal. It's just a stupid kid thing; they'll grow out of it.
Prejudices are an important tool, but don't let them distract you from Pickpocket's mental exercise.