EDIT: here’s a source for that figure
Previous studies have estimated that 73% of all antimicrobials sold globally are used in animals raised for food
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7766021/pdf/antibiotics-09-00918.pdf
6 points
On top of the other answers, animals are more likely to get sick if they get cramped together in extremely tight spaces, facilitating the spread of diseases, and meat industries do systematically cramp animals together because it’s economically efficient, at the detriment of both the animals and the quality of the meat.
