More often than not, these yobs only fear physical punishment. Now that the laws bans any one giving them a damn good hiding, or any sort of punishment at all, there is no way stop them from continuing in their behaviour. Even if you wan to tell them off, one has to go through the "proper channels" and not shout at them directly. Often, the only way to combat violence is with violence. There are only certain people who appreciate mercy, and yobs are not those people.