The Free Market?

When it comes to inflation, the newest culprit is price fixing by the potato cartel, is this something the AE community considers the free market? To me and other stalwarts of good policy like Teddy Roosevelt we see monopolies as being anti-free market and the government coming into fix the problem as protecting the free market from bad actors (in this case the potato cartel).

So… is this a good use of government intervention to protect the market or should the potato barons be able to rob us blind like an Ayn Rand wet dream?