There’s a common anarchist phrase: “no gods no masters.” Hosts are a member of a plural system who is seen as the “main” one or who fronts the most. (You can learn more about what plural systems are here if you’re not familiar: https://morethanone.info/) Hosts sometimes are considered in some capacity to be the “leaders” of a system and to have a level of decision making power or control that others in the system do not. Some systems (including us) do not have a host—there is no one system member who fronts the most, and we all have equal power over our shared lives/make decisions together—so it’s a play on words based on that.

TLDR; it’s a joke, based on the fact that we’re a plural system of a bunch of anarchists.