Some things shrink with age. Just saying.Google says the density of wheat flour is 42 pounds per cubic foot, while barley malt is 30. Meanwhile 140 pounds in that bag is nearly 3 times what I'd expect if it was full of barley malt, not just 40% more. So I'm left with either acknowledging the bag is much larger than it looks, or it's an inauthentic flour bag sporting the markings of a real bag.
(I'm looking at you, intervertebral discs.)