This seems like it would be prone to abuse. What is the advantage of transacting outside the purview of the central authority while still being subject to the p

This seems like it would be prone to abuse. What is the advantage of transacting outside the purview of the central authority while still being subject to the prerogatives of the central authority? If I strike a deal with someone behind closed doors, then that person later claims that I actually stole from them, I have to trust that the central authority will make the right decision regarding the nature of the transaction, otherwise I may end up getting retroactively screwed in the deal. The reverse is also a concern; someone could steal your coins, then claim that you're only filing a grievance because now you regret the deal. All this does is give the central authority less information from which to draw an accurate conclusion.