&gt; The problem with that is that all other methods of regulating the behavior of sellers do even worse.<p>I think this is where our views diverge. In essence what they&#x27;re doing is false advertising: &quot;buy this product because it&#x27;s at X% discount!!!&quot; when in reality it&#x27;s at a lower discount or in some cases it&#x27;s not even discounted.<p>Advertising is regulated, and there are good reasons for that, just think about an ad like &quot;smoke cigarettes, they cure cancer&quot; (granted, hopefully, an overblown example).<p>Some view free markets as a goal onto themselves, I think this is a mistake. The goal is (or should be) a good society, whatever your definition for &quot;good society&quot; is. Just because the best societies so far developed using some forms of &quot;free markets&quot;, doesn&#x27;t mean that pure to the extreme free markets would be a better means to the goal when compared to more regulated markets.<p>&gt; The definition of &quot;free market&quot; is that all transactions are voluntary.<p>That is correct, once both parties agree to the terms (price, quantity, quality, deadlines and so on) the transaction goes through.  People usually view governments (the regulator) as third (intrusive) parties to the transaction, that&#x27;s not true. Governments are representatives of the people, and as such, regulators simply add a priori terms to a transaction.<p>Historically, regulation has managed to right some (not all) of the more awful side effects of free markets, including: child labor, deadly workplaces, labor bordering slavery, labor inequality, disastrous environmental externalities and more. Is regulation always perfect? No. But then again, by your own admission neither are free markets :).