Smaller communes can successfully operate non-competitively. It seems the key is limiting membership to people seriously invested in the concept. With open societies that have large membership, competitive and power seeking forces from members uninterested in the vision seem to eventually dominate.

Didn't a lot of 'hippy' communities built like this end up falling apart from various squabbles like some people not pitching in enough etc?

Maybe https://en.wikipedia.org/wiki/Pirahã_people