A Tong can perhaps be defined as a mutual benefit society for people with a common interest which is illegal or dangerously marginal—hence, the necessary secrecy.
If a Tong is organized around a special interest (especially an illegal or risky or marginal interest) it certainly has the right to compose itself according to the “affinity group” principle. If secrecy means (a) avoiding publicity & (b) vetting possible members, the “secret society” can scarcely be accused of violating anarchist principles. In fact, such societies have a long & honorable history in the anti-authoritarian movement …
Many non-authoritarian organizations have foundered on the dubious principle of open membership, which frequently leads to a preponderance of assholes, yahoos, spoilers, whining neurotics, & police agents. Some will call this an elitist attitude, but it is not—at least not in the C. Wright Mills sense of the word: that is, a small group which exercises power over non-insiders for its own aggrandizement. Immediatism does not concern itself with power-relations;—it desires neither to be ruled nor to rule. The contemporary Tong therefore finds no pleasure in the degeneration of institutions into conspiracies. It wants power for its own purposes of mutuality. It is a free association of individuals who have chosen each other as the subjects of the group’s generosity, its “expansiveness” (to use a sufi term). If this amounts to some kind of “elitism,” then so be it.