If you believe that large supermarkets are bleeding the public dry, nothing wrong with having that as a hypothesis or assumption
Your next step would be to look at financial statements from say Tesco, and Sainsburys, and if you do that you will find that, margins have declined, thus gross/net profit is less in 2022 compared to 2021.
And so the answer is no, what you've done is just take an assumption or idea and declare it as fact, the above information i just quickly searched in 2 minutes.
You cannot put caps on food, the result of that will be people stop doing things that are not profitable. You'll go from food being too expensive, to food being scarce.
Its government intervention thats bleeding the public dry, the covid lockdowns and the resultant money printing/furlough schemes, destruction of the economy that have resulted in todays situation.
The biggest problem is the cycle of government intervention causing problems which causes people to want more government intervention because politicians manage to blame someone else, or mostly, the "other" party.