One non-nitpicky critique of the parent you replied to: under USDA labeling rules, a product may only be labeled “grass-fed” if the producer can substantiate that cattle were fed a 100% forage diet after weaning. Feeding grain, including corn during finishing, disqualifies the claim. While there is no standalone statute banning grain feeding, labeling grain-fed beef as “grass-fed” would be considered false or misleading and is not permitted by USDA Food Safety and Inspection Service.

Interesting

In New Zealand dairy herds are routinely fed all sorts of supplemental feed (palm kernel leftover from pressing palm oil, imported from Indonesia is particularly popular, with cows as well as farmers I guess) yet the products are labeled "grass fed" because the cows are kept in bare paddocks with grass underfoot.

The cows have no shade nor shelter from storms and would be much better off in herd homes, but cheapness and very little care for animal welfare