First of all, there are several protesters who have been trying to police their own and talk people down. But if the bad protester is already committing acts of violence, trying to reign him in will get you hurt/killed by either him or the cops that come for him.
Second, police have a history of using agents provocateur as recently as the 2008 Republican Convention. And historically police have targeted left-wing protests for these sorts of incitements. I'm not saying that the Ferguson police are guilty of such a thing, but it's one of the reasons why policing your own people doesn't always work. That, and the folks are really, really, REALLY pissed off.
There is much debate over I Cor 7:21. Some scholars disagree with your interpretation. If memory serves, there are two different translations of the actual text that are in direct opposition to one another. If I gave half a shit, I would look it up. But the point is that here is a religion which really didn't have much negative to say about slavery, or wartime slaughter of civilians. WTF?
While I agree that I am not bound by the OT, I think that Paul's reasoning was questionable. The law is fulfilled so we don't have to follow it anymore? What does that even mean?
BTW Paul was batshit crazy. He really thought the second coming was going to be like tomorrow. So most of his writing should be taken in that context. He advocated not getting married. He told slaves just to enjoy their lot in life. These things make a modicum of sense if the BMIC is coming back next week to destroy the non-believers and summon all us righteous folk to his fairy land.
Of course Jesus wasn't completely sane, either. He suggested self-mutilation if you were prone to check out women. Yeah, that's smart. Stick a fork in your eye instead of look at boobies. So much for being the temple of God.
Greece used something similar when trying to get people to honestly report the value of their antiquities. If they listed it for a price the government thought was too low, the agency could buy it for that price. I wish local governments would do something like that with home values. If they want to tax me for a house worth more than what I can get for it on the open market, then I should have the right to sell it to them at that price.
"Experience has proved that some people indeed know everything." -- Russell Baker