Once upon a time in a land far away on a different continent. I witnessed two men have a disagreement over a gyro. One was the proprietor of the gyro stand, the other an ostensible customer. I watched in detached interest as the customer threw his gyro across the counter at the proprietor. Who promptly came out from behind the counter and began whipping the ass of his, past-tense, customer, with one of those relatively long bendy spatulas you might use for scooping meat off of a grill. The 'customer' went down and the proprietor bodily drug him out into the street and threw him out, after delivering a short kick to the ribs.
I continued to each my gyro and fries (it was delicious) and tipped the proprietor on my way out for the good show.
In other words, I fully agree, stay the fuck out of it. I stayed the fuck out of it, not my monkey, circus, county fair, country, or language. No clue what was said, since it was in a language I am not fluent in, but it clearly wasn't polite. Regardless, the matter was resolved quite rapidly without significant damage to either party and it was simultaneously entertaining to watch.
I fully agree. Which is another reason why I don't think there needs to be any special legislation in this realm. I concur with @Trooper224's assessment that there is ideological merit to the ideas proposed in the OP, but promotion of such a mindset is needless and dangerous.I find the entire possibility vanishingly small in the US and an extremely foolhardy thing to insert yourself in to physically if it did.
From a purely academic point of view - If one were to find oneself in this, exceptionally unlikely, situation and if one were inclined to insert themselves into the situation, I believe that the justice system could separate out the good and bad actors. Partly, because the situation would have to be so extreme and extenuating that circumstances surrounding it would be thoroughly investigated and partly because if you (universal) were inclined to get involved for whatever set of reasons, you'd damn well better be able to articulate your decision making chain leading up to it.