While true, I think the point here is that Loblaw collects a high margin irrespective of the beef's cost to make. But yes, the cost of meat has been historically absurdly low. Another example of the market not pricing in externalities.

People buying the premium cuts pay for the cow. Ground beef is the parts they can't sell as steak or roast or stir fry

It should be cheap

Low fat ground beef should be a little more expensive as trimming the fat before grinding takes skilled time