Any system with buyers and sellers is a "market", that's a meaningless standard. If all of the insurance companies in the US decided to merge and use their lev

Any system with buyers and sellers is a "market", that's a meaningless standard. If all of the insurance companies in the US decided to merge and use their leverage to lower drug prices, it would be an illegal cartel. The resulting price would be the "market price" but not the price that would exist in a free market, which in most definitions includes prohibitions on such cartels. Governments can get away with it because they write the rules and there's no higher authority to stop them.