> Loners would be taken care of by the state. They don't wither.

How? Where does the state take scarves and tomatoes from if we only produce as much as we need within our own circle and exchange them solely among friends?

This is not as trivial question as it may sound. In the USSR, where I grew up, this was classified as a crime of "speculation". People were jailed and their property confiscated to intimidate others to work for the state without bypassing the forced redistribution.

The question of gifting a scarf to a friend, when someone else might need it more, is in disguise, the central question of communism. There is no way to preserve my freedom to give the scarf or other fruits of my labor to whomever I please (or keep it for myself) while simultaneously satisfying the needs of those whose needs are unmet. There simply aren't enough scarves to make everyone happy. If you try to coerce me, I won't knit any scarves at all, or they'll be of very poor quality.

This is essentially how and why the USSR stagnated for decades until it collapsed under its own weight. By the end, despite coercion, productivity had fallen so low that people with physical access to goods (like truck drivers) resorted to bartering, while others (like university professors) starved. The all-powerful state that was supposed to "take care of everything" was nowhere to be seen; they were busy bartering tanks for chicken.