To me it all boils down to force. I’m ok with people deciding to form an anarcho communist community so long as they don’t want to force me or others to be involved. Anarcho capitalism does not say people can’t form into whatever system that they want to. All it says is that IF one does not chose it, you should not force them.
Even though anarcho communist sometimes don’t say they are socialist it seems to me that what they are advocating is Karl Marx’s final phase of socialism. That is where the state withers away and you are left with communism.