Maybe a well-organized Book Club. That might just work.
And be just as ludicrous an interpretation as your first. Book clubs are formed to benefit the club members, but the club members don't exist to benefit the club.
You cannot have a collective right to do something that the individual members in the collection do not have individually. A Militia is simply the right of individual self-defense exercised with other individuals in a group setting, for mutually beneficial purposes. The Militia has no rights of its own; it exists to serve the purposes of its members, not vice-versa. So, how can a non-infringable right exist to only benefit the Militia and not the individual needs of its constituent members?