There's nothing in the scenario described by Xyrik, or the scenario described by Tem42, that says the people involved are doing only "meaningful conscious-expanding profound activities" and neglecting the necessities of life.
The whole point of the communist paradise is freedom from need. That, as you correctly point out, leads to an incentives problem and a coordination problem. The lack of incentives (which, I think, exists in Xyrik's scenario as the alternatives are... much less palatable) leads to people over-doing pleasant things (meaningful, profound, conscious-expanding -- or simply hedonic) and under-doing unpleasant things (e.g. mucking in the dirt). At the current level of technology a society without appropriate incentives will soon start to starve.
It works for small communities which mooch off larger societies (hippy communes, Burning Man, etc.), but convert the entire world to this system and I would recommend getting a lot of ammo and beans ASAP.
The problem with that viewpoint is that you assume that the only reason - or, even, the most important reason - that people work is to make money.
But our understanding of human behavior tells us that other factors like status games, feelings of personal achievement or 'having a purpose in life', and so on are equally as important, if not more important, than the money-making aspect of work. Further, something that someone considers 'work' could be considered enjoyment by someone else.
Believe it or not, many people farm or tend gardens or animals simply bec...
How much money would it take to engineer biological immortality for at least half of the world's population, within 20 years, with 99% confidence?