@lowca
What I meant was that for a small price, extra, unattended, heavy, or extra luggage can be loaded in the hold by the handlers. it is probably done everyday.
As you can see from another poster in France, the rule doesn't even exist there.
The flight crew would have have zero knowledge of any extra or unattended bags.
Having spent a lot of time in that part of the world flying commercially, unfortunately, I have seen things like this occur.