(little bit confused by your first sentence, I definitely do not support shooting people for stealing ones cat converter, just for clarification)

So if the police are useless and you are beholden to this powerful and highly organized pack of thieves, you think going out there and shooting them is going to make your life any better? What happens if you don't 'get' them all and now you're in a shootout with multiple armed opponents? What about the rest of their organization, reckon they will let you get away with it? Personally, I'd rather have my car temporarily damaged.

What can an average citizen do about their safety net in the US? Probably a whole shitload, anywhere from political participation, union involvement, volunteering, voting for politicians that support a better safety net.