Is it "good" to maximize economic output? Does capitalism attempt to maximize output? Are the restraints placed on capitalism justified if such restraints maximize output?
If you answer yes to all, then we share enough common ground to continue.
One end result of government is that currency has value. People only use currency if they think it has value. Currency has value only if OTHERS think it has value. The net effect of a person and others agreeing that a mostly useless shiny bead or piece of paper has value only comes about if they agree to be governed by the idea. That's government.
The D2 currency was established by the users of D2 wanting to establish a currency. The players wanted to be governed so governed they were. Enough players agreed on the various currencies that others followed suit. What type of government is that? That's a very good question. It's probably a mix of laissez faire capitalism and anarchy and emulator of .