...I wonder why those and not the others?
My understanding from what I have read from users that described the issue has more to do with the decisions made when these reproductions were initially made. Those like the 1892 which have it and were made by Miroku before others initaily had it and now it's stuck with it. However later when coming out with the 1866 or 1873 they decided not to and so it doesn't. So for some reason whether legally or for reasons of liability the 1892 is now stuck with it. I don't know for certain and I am just relaying what others have said.