he don't and he doesn't

In The lord of the rings movie,my teacher found-"he don't" my question is why the author using "he doesn't" is it just licenci poetica or has another meaning that related to the British culture?

[Mister Micawber]

It would be better if we could see the actual quotation, Ice, because I don't have a copy handy; however, I suspect that Tolkien (or the scriptwriter) used it as character colouring. Both hobbits and orcs, for instance, could be portrayed using substandard English, to represent ruralism and savagery, respectively.