What does this mean?

Anyway, I see your point about the American actions.
It may have to do with perceived quality of the euro actions in general or that many Euro makers have a long history of building cape guns and extra rifle barrels on their actions - so there is experience using these actions in that respect.

Also, from what I have noticed on the used shotgun market, the Euro guns are more likely to have a pistol grip stock which is preferable on a double rifle.

Where in CO are you located?