But many animals eat other animals. Is it better because they don't have the mental facilities to process the morality? Is morality really objective to begin with, or is it just another human thing?

It's not that there's nothing wrong with the food industry, but to say killing to eat is morally wrong without going into the murky details is a bit dishonest imo. I think it's fair to put humans on a higher standard, but literally nobody knows what the long term consequences, across many generations and demographics, of switching off of meat entirely, would do. The default option is to just keep doing what we know works. Meat works, again ignoring the issues with the food industry unrelated to the underlying morality question.