I live in Algester, Brisbane. There is absolutely no place near here that as a high crime rate.
As for there being a place for a "dark knight" - no. Batman is fictional. No one, NO ONE could do the stuff he does or do it with anywhere near the accuracy or the talent. Anyone who tried to ape Batman in real life would either 1) Get killed or 2) Kill others.
Batman never kills - but that's because he's a fictional character. All those punches and kicks he does in the films? In real life, they have a chance of killing someone. Your brain is pretty fragile, and you can develop a cerebral hemorrhage just from hitting the concrete with your head. Given the amount of thugs Batman has punched and knocked down, I can guarantee you in real life, at least one of them would have died due to head trauma.
Batman's actions in real life would almost certainly result in deaths - deaths he would claim are justified, but how are we to know? The Justice System is in place because we can't trust (or shouldn't trust) authorities and their word. Cops can be crooked, you know.
Now, we trust Batman because we've seen his backstory, have access to his inner thoughts in the comics, and can see all his actions..... because he's a fictional character on paper/TV/Film. If someone in real life decided to do the stuff he did, how would you know he was on the level? How would you know that he was as good as he says he is? You can't.
Justice needs to be ordered and needs checks and balances, otherwise you're just letting self-proclaimed "protectors" do whatever the hell they want in the name of their version of "Justice". That's why vigilantism is illegal, and should be illegal.