That's also very misleading because the vast majority of the corn we feed cows isn't fed to them fresh. It's distillers grains, an industrial waste from ethanol production: https://en.wikipedia.org/wiki/Distillers_grains

It's a cheap type of corn [1] only grown on marginal farmland that is one step above pasture land.

[1] https://en.wikipedia.org/wiki/Dent_corn