So what? The demand for food is inelastic—all humans need a decent amount of it and you can’t buy it used. Demand can never drop below a certain level, regardless of the price being charged. So regardless of how many companies are involved, they’ll make the most money by keeping the prices high. Actual competition doesn’t benefit them.

You could replace the full text of any grocery company’s press releases and interviews these days with “Qu’ils mangent de la brioche,” and express the same thing much more succinctly.