Flour spoils much faster then unmilled grain. So the bulk of the grain would always be left as grain for storage. Armies would be the ones who would want to bul

Flour spoils much faster then unmilled grain. So the bulk of the grain would always be left as grain for storage. Armies would be the ones who would want to bulk mill an entire harvest taken from a region. For those without access to windmills, the daily grind would produce flour/ meal for that day.