Hobbesan Social Contract theory posits that we agree to give up our rights to violence against each other and give it to the State, on the grounds that the State, as a third party, can use a monopoly on violence to make its citizens safer, happier and more productive, as they can go about their day worrying about other things than the possibility of their neighbours making war on them and taking their things. Without it, things such as private property, industry, art and other higher functions of broader society are not possible, as we would degenerate into the state of constant tribal warfare as we were 7000 years ago before we formed urban societies.
There are problems, however. One is that the state cannot be everywhere, all the time, and we may be subject to violence by criminals. Most countries therefore allow citizens to engage in limited violence in self-defence.
The other problem is people like Andy Ditch. The solution to Andy Ditch, logically, is violence. He is the kind of parasite who has no value, and his behaviour would be corrected by a judicious application of violence. But the Social Contract forbids it. Ditch is wily enough not to break the Social Contract without breaking the law. Therefore society and the law do not visit violence upon him, and forbid others from doing so. So Andy Ditch behaves in a way that is just as disruptive to society as crime, in many ways more so, in terms of the burden that he places on others. But to make exceptions to the law to allow violence to Andy Ditch would start to erode the Social Contract. Updating the law to make what he is doing illegal is theoretically possible, but in practice people like Andy can subtly alter behaviour to stay on the right side of the letter of the law while still disrupting society.
In conclusion: Society is doomed because we cannot issue the beat-downs Andy Ditch and his like require.