Yeah I was gonna say, they aren’t just outside eating the grass off someone’s lawn once in a while. They are endlessly devouring specially made feeds
No, just no. Most horses are not fed grains of any type. They eat grass and hay. Grains aren't really great for them anyways. Performance horses and elderly horses will get supplemental style grains, but a horse needs to basically eat 24/7 to keep their guts properly working.