Choose your battles

There's a cool show I like to watch when I think of it called "What Would you do?" It's an odd twist on the old Candid Camera show. Situations are staged that cause on-lookers to make a decision to intervene or not. Situations like a blind person given the wrong change in a store, at an open house visitors steal things, an upscale store is obviously racially profiling, or gay men are openly affectionate in sports bar. Sometimes no-one stands up to defend the victim. So, they ratchet up the actor bully role until someone simply can't stand it any longer and intervenes. I feel bad for the person who is duped in the story - the one who speaks up. It's always emotional. It kind of bothers me that they were tricked.
But it does pose a lot of questions for me beyond what I would do in the given situation. I wonder, is it easier to stand up for strangers in a situation that appears clearly wrong? Somehow, it seems so. We can speak up. Feel good about it. Walk away and never see those people again.
The battles that rage among our friends and family are much more difficult. We all see one another a lot. We will cross paths again and again. The context of the battles are so much larger. And the lines are much less black and white.
Perhaps the battle then should be to find a way that lifts all parties up. How do we do that for the person who is purposely giving the blind person the wrong change? What if the person doing that misdeed was your brother or your friend? Would it make a difference in how you handle it?