Almost every successful "side hustle" comes down to arbitrage buoyed by who you know.

That doesn't make this any more or less "free" market. Negotiating deals are common in every type of economy.

Is insider trading just a kind of arbitrage too? :-)

Yes, the free market. The commodities biz has an old adage; “long-term contracts solve supply problems; spot prices solve inventory problems”. This is a clear instance of the latter. Arbitrage is an essential facet of marketplace correction, it’s practically the first derivative of pricing. One may also see it as a reminder that economies are a gestalt.

Why do you say that? Command economies arent exactly known for being free from personal dealing either

That comment is seeking to manipulate, not inform, its readers. I flagged the comment because it's not appropriate for HN.