Structuralist buildings express interaction between people and often also play with dichotomies, such as inside/outside, nature/machine, etc.
Translated into a bag: just as a structuralist building expresses the interaction between people within the building, the structuralist bag will reflect the way objects live within the bag.
Pockets, which are usually on the inside of a bag, are brought to the exterior. Though there appears to be many pockets from the outside, inside, they are actually joined to become one large pocket. This represents that we try to organize our objects using pockets, but eventually, they become disorganized.
These pockets will not be accessible from the outside, and cannot be detached. This represents the permanence emphasized in structuralism.