Actual anarchy isn't simply No rules (that's just chaos and isn't even remotely sustainable), it's when there is no centralized legal system and enforcement, there still very much are rules that are expected to be followed, which are enforced by the group as a whole. Obviously is a very simplified analogy to how it works.
Almost like if there were a union of 50 states, and each state had slightly different laws. Mostly they're the same, but if you're not careful you could run amok and ruin your life with a random felony.