Like Bryan, I really enjoyed Jason Brennan's discussion of "Why Utopia is Capitalist." Bryan is correct to note that one of the main problems with G.A. Cohen's camping trip example is that it assumes (albeit implicitly, if I remember correctly) that we have all decided to go on a camping trip together. It's basically a question of constitutional choice: what kinds of contract do we wish to adopt if we are all going camping together? It reminds be of Peter Leeson's work on contract and governance among pirates (he explains it in a 2007 Cato Unbound symposium).
As Brennan writes, capitalism is preferable to socialism because voluntary socialist experiments like utopian communes and socialist camping trips are possible in a world with private ownership of the means of production. Capitalism tolerates socialism. Socialism does not tolerate capitalism.
For the last few weeks, we've been getting together with friends from church for potluck lunches on Sunday afternoons. These are "socialist" ventures like Cohen's camping trip, and I think most of us would agree such gatherings are integral parts of a robust and thriving civil society.
What if we went around the neighborhood and instead of inviting people to lunch we tried to jawbone people into joining us out of moral obligation? What if we started trying to conscript people into our Sunday lunch gatherings? Most people would find such behavior boorish, intolerant, and once force is involved, evil.
Capitalism accommodates diversity in ways that socialism simply cannot. Naturally, one might respond that with the advent of the New Socialist Man, concerns about different preferences will be beside the point. I'm reminded, therefore, of a joke:
A revolutionary is giving a speech to a large audience, and he promises the assembled masses that once the revolution comes, the land will flow with milk and honey. He is interrupted by a gentleman a few rows back, who asks "what if I don't like milk and honey?" The revolutionary responds: "comrade, after the revolution, you will like milk and honey!"