My repo front fenders are the same way. I got them for free (very good friend bought them).
My guess why they are made like this is, since the front lower corner is all that changed on the 54 & 55 1st series fenders, the didn't have to make 2 complete molds for the fenders.
By doing it this way, 1 mold for the fender itself, & 2 smaller ones for the 2 different corners.
