I guess when the law offers no protection for your virtual weapons, all that is left is to take matters into your own hands. In massively multiplayer online role-playing games (MMORPGs), virtual economies actually evolve. For example, in Everquest, the monetary unit the "platinum piece" was actually trading at higher values than many world currencies, some equipment in the game would fetch hundreds of dollars, and high-level accounts would fetch thousands. None of this is condoned by any of these games, though I find it hard to believe the companies wouldn't want this great marketing for their games. It's just a legal issue.
MMORPGs and virtual economies began with Ultima Online, in which people even owned virtual dwellings and land. I'm surprised, if they haven't, that economists aren't using these virtual worlds to study economics and the rational choice.
I quote from the story, "After Zhu refused to return the item or pay compensation, Qiu went to his home and stabbed him in the heart, according to the report."