All of it. Anarchism is much more accessible by osmosis than most other leftist philosophies, because it doesn't have the same level of propaganda levied against it that communism does. The anti-anarchist propaganda focuses mainly on it being a "DON'T TELL ME WHAT TO DOOOOOOO!" kind of "philosophy" which is appealing to impotent manchildren and edgy teenagers. Some of those people then actually read anarchist theory and realise it isn't about that at all, but a lot of them, like libertarians, just want an excuse to be a spoilt brat of a human being who wants everything handed to them and a bastardized version of anarchism is a quick and easy way to do that.

Let's not shit on the anarchists too much. We marxists also got plenty of fucking wierdos and patsocs and other kinds of morons. This is mostly just the consequence of the terminal lack of rigorous materialism in the thinking of western populations.