As I understand it, you have to remember the time those locks were created: The United Kingdom that meant Africa, India etc. Carrying your gun/rifle in these tropical climate it was an advantage to be able to drop them out or replace them.
If I lived in those times I would have carried of course some extra locks with me as PM wrote. Time and countries needed some "spare wheels" ;-)
In the book of Westley Richards there are several guns and rifles with extra locks in a nice and practical leather bag.

Gunwolf

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