Taking scarcity out of the equation, you could still get huge fights and very unstable communities.
This is what I tried to say. The scarcity is a problem in itself, but it is not the true reason why we don't have utopias.
Usually there's some more or less dubious theory that points to a group of bad guys and jumps to the conclusion that removing the bad guys will create utopia.
Yes, this model is very popular, because it allows one to work altruistically for the benefit of humanity, while getting a lot of power and a freedom to kill people they dislike as a bonus.
But there are also other models. Having enough money, one could just build a new place and only let the good guys in. No need for killing, you just need one enthusiastic millionaire to sponsor the project. If the new place is small and not isolated from the rest of the civilization, the people can still participate in life as usual; they would just have their community as a bonus. Actually, people can cooperate and share their property even without a big investment, if they live reasonably close to each other. They just need to define that X, Y and Z are members of the community; they all share property with each other, but don't share with the outsiders. That's it.
Again, I think the true reason why this does not happen more often, are the interpersonal conflicts. People living in the utopia usually realize that they don't like it... although they would like it, if they could replace their real human neighbors with the preferred kind of imaginary people.
Sometimes the utopia proponents admit that their utopia would require "education" of people. But to me it feels (maybe I am too ungenerous here) that they consider themselves ready for the utopia, and it is just the unenlightened masses who need some brainwashing. Also I see a problem here that without some "pilot project" how will we test whether the proposed education works for the utopia or not.
I would like to see more people who have their ideas of utopia, but who admit that they could be wrong and that their ideas need to be tested experimentally first. Then we could have a Scientific Utopiology, which would be a huge improvement from the usual "mass murders first, realize the obvious (for unbelievers) problems later".
I've had many ideas for possible utopias, and read about many more, but I seem to always stumble on the same problems (or if I don't, someone else usually points out (correctly) that my solution for one of these is flawed):
Expertise verification. How do I know that you know what the hell you're talking about? (having members of the society all trained in hardcore bayesian rationality would help, but obtaining evidence that another rationalist has the evidence that they seem to have or claim to have is still costly, and arguing to an aumann agreement can
Assume for the time being that it will forever remain beyond the scope of science to change Human Nature. AGI is also impossible, as is Nanotech, BioImmortality, and those things.
Douglas Adams mice finished their human experiment, giving to you, personally, the job of redesigning earth, and specially human society, according to your wildest utopian dreams, but you can't change the unchangeables above.
You can play with architecture, engineering, gender ratio, clothing, money, science grants, governments, feeding rituals, family constitution, the constitution itself, education, etc... Just don't forget if you slide something too far away from what our evolved brains were designed to accept, things may slide back, or instability and catastrophe may ensue.
Finally, if you are not the kind of utilitarian that assigns exactly the same amount of importance to your desires, and to that of others, I want you to create this Utopia for yourself, and your values, not everyone.
The point of this exercise is: The vast majority of folk not related to this community that I know, when asked about an ideal world, will not change human nature, or animal suffering, or things like that, they'll think about changing whatever the newspaper editors have been writing about last few weeks. I am wondering if there is symmetry here, and folks from this community here do not spend that much time thinking about those kinds of change which don't rely on transformative technologies. It is just an intuition pump, a gedankenexperiment if you will. Force your brain to face this counterfactual reality, and make the best world you can given those constraints. Maybe, if sufficiently many post here, the results might clarify something about CEV, or the sociology of LessWrongers...