Ever wonder why Sam calls Frodo “Mister Frodo” or "Sir"? Well, that's because he was Sam's employer. What job did Sam do for Frodo?
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Inherited from his father, Hamfast "Gaffer" Gamgee, Samwise Gamgee was Frodo Baggins' gardener, and a good one at that if we do say so ourselves! That explains why he used certain formalities when addressing Frodo.
Asked by Rachel Bortles · Last updated 5 years ago · 5.7K views · SOURCE