We don't believe people are naturally cooperative, but that humans are a product of their material conditions. Everything that came before us weighs on us like ghosts of the past. Humans are neither inherently good nor bad, cooperative or individualistic; they work in their environment and social relations. Capitalism rewards greed and individualism (especially rejecting responsibility when something goes bad), and so people learn to become just that.
Maybe think of it this way: take a product that you like and consume regularly... Coke, ketchup, whichever. If that product had never existed, you could not want it because you would be incapable of imagining it and thus imagining wanting it. In socialism, where there is no exploitation and profit motive,
My question I think would be what, in your opinion, prevents communism working above a dozen people? We have seen socialism in the USSR, in Cuba, in the DPRK, Vietnam and the PRC. They are not yet to communism but they are certainly doing great (Cuba especially) and they are not dozens, they are millions. We see in Cuba that people relatively want more consumer goods -- not helped at all by the embargo coupled with seeing so many products in American media that are simply presented as an absolute good because "more choice is good, keep consuming", and the environmental impact, the commodity fetishism of these goods is never discussed -- but overall, they don't wish to exploit their fellow human beings (profit off their labour-power) or go back to a time where that was the norm (pre-Castro Cuba).
I also don't understand how writing stories does not benefit others. The article I linked at the end for example really informed my view on prostitution. We are having this conversation now only because I wrote something that you read. I can't speak for everyone but writing is a hobby to me and I wouldn't want it as my job to be honest.