North Europe here. Myself & my kids may consume at least 1 liter of milk per day up to multiple liters (with cereal, or just drinking it or making food with it). Not counting all the milk-products we consume...

In time of poverty, cow was actually essential part of life. A life saver. You get milk, butter, sour cream, cheese, cottage cheese. I think not every word from this list makes sense to some living in some other countries, because not all products are consumed in other places in the world.