Aren't anarchist groups and meetings defeating the point of anarchism?
I don't know about the US of A, but here in Europe anarchy is defined as a lack of social hierarchy and government, not rampant individualism. It usually implies living in communes, collectives and syndicats.
So an anarchist group, even a well-organized one, is no oxymoron. A selfproclaimed leader of such a group on the other hand...
I'm personally a fan of large scale complex civilization. There's a reason people all over the world developed states and administration as soon as they settled down and practiced more complex agriculture: cooperate to plant rice (which as far as I know, requires lots of helping hands and can not be done by an Individual or a small family), save some grain and organize things around the flooding of the Nile, control watering rights so everybody gets a fair share, etc. Add organized defense against outsiders as well as somebody taking care of keeping the streets save and you already have yourself a tax collecting, law imposing state.
Even hunter-gatherers hunt and gather in groups, take care of the sick and old, help each other out and follow tribal laws.
Thoreau style individualism in a cabin in the woods is not an option for our species, only for a handful of individuals (who, as had already been said would be freeloading on the work of others and/or dramatically diminish their life expectancy and quality of life).