Today I found out why crackers have holes.
Surprisingly, it turns out the holes are there for a reason, not just for decoration or for convenience in some manufacturing process, as one might expect.  In actuality, without these holes, crackers wouldn’t bake correctly.  These holes allow steam to escape during cooking.  This keeps the crackers flat, instead of rising a bit like a normal biscuit as the steam tries to escape; these holes also help to properly crisp the crackers.
When crackers are made, dough is rolled flat in sheets.  These sheets then travel under a mechanism containing “docker” pins that end up putting the holes in the dough.  The hole’s positioning and number varies depending on the size and shape of the cracker.  If the holes are too close together, the cracker will end up being extra dry and hard, due to too much steam escaping.  If the holes end up being too far apart, parts of the cracker will rise a bit forming little bubbles on the surface of the cracker, which is undesirable in most types of crackers.