https://www.youtube.com/watch?v=A7hCw5Q8qGw
I enjoyed watching the video just because it gives an idea how big one of these company's warehouses is. (Best view starts about 0m55s.) Those are some tall shelves, and there are a lot of rows of them.
They're supplying probably millions of people with food, so it makes sense, but I still found the visual impact interesting.