It is probably more a result of the fact that the M-6 was made for the M-14 Rifle, which was fully automatic. Ebay has been restricting sales on any parts for fully automatic or the more nebulous "assault" weapons. It's often random and silly what gets taken down and what doesn't, especially considering that an M-6 bayonet isn't functionally any different than any of the thousands of bayonets sold here every year. But then, common sense has never been the "Ebay Way".
Another possibility is you ALWAYS need to switch off overseas sales on bayonets as this will also get them taken down. Many countries don't allow the importation of bayonets, even antique ones.
