A couple of years ago I bought an Over/Under Merkel double shotgun built in 1953. It has ejectors. There is also a fitted BBF barrel set, made by Krieghoff in 2958, in 16ga-7X65R. That barrel set has ejectors also. I figured it was a one-off, where Krieghoff made the ejector set simply because the parent gun had them. But this week I bought a Merkel BBF, same action as the shotgun, same combo calibers, made completely by Merkel, and it too has ejectors. What is also interesting is that the shotgun barrels almost drop and lock into the second BBF action. In my 50 years of combination gun interest, this is my first experience with ejectors in combination guns. Are these rare, or have I just not been exposed to the upper echelon of combination guns?  For photos, see it on gunbroker here:  
https://www.gunbroker.com/item/1135526740