I'm betting some assclown sitting in the back of a store after hours when the shipment came in, switches out some crap winchester for CCI in a few boxes out of each brick from a case, then sold himself some CCI disguised as Winchester, saving a few bucks.
I doubt it. The only place I've been seeing Winchester is at Dick's, selling for the same price as CCI.
If they got mixed at the store, more than likely a pallet or U-boat fell over, the ammo spilled out, and the employees put it back in the boxes/containers without paying close attention.