Design over substance
I’ve noticed over the years that Sharpies love their interestingly designed boxes. I assume that they do it to show off the colors of their pens, but there are always fish, or dinosaurs or butterflies painted large across the front of their packaging.
Perhaps the extra space they take up is so that they can be more creative because it’s definitely not necessary for the number of pens that are inside. This one has 28 pens in it which, as you can see from the photo in the bottom right, take up less than a quarter of the box space. This really is so wasteful.