As I read through this thread, I was waiting for someone to answer this question. As no one did, I'm going to take a stab at it. During the Great War, there was some anguish by pilots (especially Brits, as I recall, though I could be wrong) that the symmetrical application of national insignia on the wings gave enemy pilots a perfect aiming point. The pilot was smack in the middle. So, various experiments were carried out to see if changing things up threw off the bad-guy's aim. Of course, in the end, it just didn't "look right", so the original application was retained. I'm guessing the Poles got the message and weren't as worried about how it looked. The asymmetrical application of insignia was meant to throw off the attacking pilot's aim.
I'm just shooting in the dark here (get it?), but I think that's why they did it that way.
Michael