The desillusions people seems to have here is the same kind you have for religious people and moral, where the religious people claim that religion is what provides moral, and hence non-religious people cannot know right from wrong. It seems that in the same way, people in this discussion have defined that communism is the mechanism for being generous and being willing to contribute to society. Hence, all non-communist societies cannot exists, since nobody will build it. Basically, it is a very brainwashed take on communism, not based on anything existing but on some fantasy, especially since all practical attempts at communism seems to requires to strip people of all their freedoms.