Yes, the word communities should remind you of the word communists. Both share a Latin root called 'communitas' meaning common (as in general public). It is the same root we find the 'communion', in the church and stuff.
I think a guy in France in the late 18th century organised the first communes in which people lived together and shared (nearly) everything together. St. Simon's utopian socialist communes, I think they were called
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And what do you mean by 'special' communities
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As for the toilet drinking, well, I don't see how this is relevant to the game at all. It is really
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and something you would expect to see in any other game than a Fallout game. And the person who thought of this should get this (symbolic)
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treatment.
Drinking more than 200 year old toilet water, probably brown and stale and fested with all sorts of bacterias as well as mouse and rat dung should really make you sicker, not heal you in any way shape or form. Fresh water sources like streams deep within mountains or perhaps in the subway systems should heal you a little, I think. But the really big healing should come from eating your stimpacks or taking your radiation pills.
I, for one, don't see how this is innovative and immersive, not unless Beth really wants to make some sort of simulation game, where 'realism' is the king of all things, and not a Fallout game which relies on the retro sci-fi future people dreamed of in the 1950's i.e. not the actual 1950's, but based on how the people in 1950's imagined what the future would be and look like.