That's not exactly a strong indictment: when the average margin for the industry is about 1%, all kinds of things are going to cause this or that industry participant's margin to fluctuate up or down by a factor of 50%, i.e., to go down to 0.5% or up to 2%.
It's not the same thing as Apple's margins, which last time I checked 12 years ago or so hovered around 33%, so if they went up by 50% (i.e., to 50%) it would mean something (at least if they stayed at that high for many years, which BTW you have not mentioned whether the largest grocery chain's did).
That tracks with their financial statements (no new efficiencies).
So, the only way to increase profit margin when input costs are rising is to raise prices more than your costs are rising.
As an aside... Loblaw's margin is upwards of 3.7% not 1%. Before Covid it was around 2% (give or take) for over a half century. The grocery industry may have low margins but they were remarkably stable. Until Covid.
Instead, your analysis is simply: "Government bad!"
Don't get me wrong. I'm not saying the government isn't a very large part of the problem (ie for increasing the money supply and a lot of the things you mentioned) but to try and explain what happened to food prices without even mentioning Covid, or record corporate profits, is extremely disingenuous.
But damn those "economically illiterate" serfs complaining about high prices, eh?