Anarcho-capitalism is an oxymoron. You need hierarchies to protect private property, otherwise the whole thing just collapses on itself because there's no significant force to prevent theft - and not just by communities, be it states or cities, not following the principles of that selfish flavor of liberalism.

Even if everyone lived in an "ancap" dystopia, that doesn't make everybody magically immune to greed, and some would happily bend the rules and loot, kill or steal, even if they agree on the social contract.

I really don't think these idiots deserve the label "anarchism". I like to go with "neo-feodalism" because this is what their dystopias can only resolve to ultimately as soon as wealth is concentrated enough (which is inevitable without corrective action currently undertaken by the state in normal societies).

I'm not saying this for you as much as I'm saying it for the lemmings that might not be too familiar with their nonsense.

For one illustration of the dangers of their stupid ideology, see https://www.vox.com/policy-and-politics/21534416/free-state-project-new-hampshire-libertarians-matthew-hongoltz-hetling