Because "free trade" does not exist unless all regulations go away. But American mega corps (which includes political parties) like to pretend free trade means just get rid of the regulations we don't like, but keep all the ones that prevent competition.

Rent control is not even close to the only barrier to the free trade of housing. It's one of the most minor, but its one of the few that actually protects consumers verses protecting the interests of mega corps like most regulations do. So of course the mega corps are opposed to it.

I think the words "free trade" are a bit overloaded, at least in the way OP used them. I am very much a globalist and think free trade between countries is very important. I am also very much against unregulated markets (which I assume is what OP meant by "free trade", i.e. free trade / unregulated market on the scale of a city and its housing market).

I don't find it hard to be against free trade. All you have to want to do is protect your own model because you believe in it more than another. I don't believe in many foreign labor laws, so I don't think those goods should be priced the same as goods produced under different rules. I would rather the products were produced by robots under better conditions. I hold a similar view of capital. Of course it is easy to agree with free trade if you don't attach any consequences to it.

The US has economic sanctions against Cuba, North Korea, and Iran. https://en.wikipedia.org/wiki/Economic_sanctions#Current_san... lists other countries similarly opposed to free trade.

I'd strongly recommend Ha-Joon Chang's Bad Samaritans: The Myth of Free Trade and the Secret History of Capitalism:

Chang argued uncomfortable truth of capitalism and criticizes globalization represented by the book "The Lexus and the Olive Tree" in the first chapter. He argued that there are errors in theories regarded as established theory related to economic development and refuted them with economic theory, and historical and current data. In the later chapter, Chang claimed that "Market and democracy clash at the fundamental level." In epilogue, he wrote about Brazil in 2037 that faced gloomy future as a consequence of reckless beliefs in neo-liberalism policies. Finally, he made the case for new strategies for a more prosperous world that may appall the 'Bad Samaritans'.

https://en.wikipedia.org/wiki/Bad_Samaritans:_The_Myth_of_Fr...

An interesting digression of views is evident in a dispute between publishers of the English an American editions of Chambers Encyclopaedia:

Free Trade (American Edition), 'a dogma of modern growth, industriously taught by British manufacturers and their commercial agents. For many years certain political economists have laboured to establish this theory upon a reliable basis, and have asserted that the doctrine represents an important truth; but no nation has attained substantial prosperity except by protection to native industry, whether avowed or disavowed. The doctrine had no foothold in the policy of any nation, and had no legislative birth until put forth by Sir R. Peel in 1846. While it was in the interest of Great Britain to protect her industry, she imposed sufficient duties; and when, by this means, her producers of wealth became strong, and able to compete with those of other countries, protection yielded to reciprocity; and even at the present time, the nations most clamorous for free trade rely upon it in theory only, reciprocity in fact, and protection in principle. Even the most strenuous advocates of the theory dare not put it to the test of experience in its fullness. The teachers, therefore, remain self-deceived. The cloistered sophists of their schools, and the propagandists of free-trade, are doubtless as learned as the sophists of any age, and practically as useless. Free-trade expressions need Americanising, as they are utterly hostile to our prosperity, and subversive of scientific truth. Whenever an advocate of this dogma, schooled in their errors, has found devolving upon himself the responsibility of dealing with practical questions, he finds their supposed cardinal truths as groundless as the mythical Arcadias and Utopias of romance. The sophistries of free trade are put forth to lull the suspicions of the deluded purveyors to the wealth of England, and are advocated most strenuously by agents of British manufacturing houses and foreign residents in our cities, whose chief aim is the accumulation of wealth by extensive sales of foreign products, regardless of the injury they may inflict on American interests.' With a great deal more on the same purpose --- an entire perversion of the original.

https://old.reddit.com/r/dredmorbius/comments/4xe2k1/chamber...