Fanarchists
from Fancyclopedia 2 ca. 1959
(1) Genuine anarchists who are also fans; New Yorkers, mostly.

(2) Those who oppose the existence of general, or even regional, fan organizations on the ground that people are congenitally unable to form an organization that does not involve the abuse of power… not in the sense of an individual's lust for power but in a different way which results from group action itself and vitiates the most enlightened decisions, with the viciousness of any fan group tending to be proportional to its size.

Fully articulated this doctrine is a species of rugged individualism which asserts that fans acting singly or in small natural groups of a few fen linked by common interests can achieve more, for a given amount of work, than thru a large and cumbersome organization. Their attitude is mainly a reaction against the uncritical organizing instinct of young fen who say we gotta organize to get things done and in organization there is strength and an organization will help coordinate us, without having any but the vaguest idea of the referents behind their words, and often trusting in false analogies.
from Fancyclopedia 1 ca. 1944
Those who oppose the existence of a general or even regional fan organization on the grounds that it has insufficient functions to justify the work involved. They accept the desirability of locals. Fully articulated, the theory is a species of rugged individualism which asserts that fen acting singly or in small natural groups can accomplish more with the same amount of work than they can thru a super-organization. Their attitude is mainly a reaction against the uncritical organizing instinct of young fen who say we gotta organize to get anything done and in organization there is strength and an organization will help coordinate us, without having any but the vaguest idea of the referents behind their word, and often trusting in false analogies.

Also, specifically, dissenters from organized British fandom.