They are not locals, as we infer from their lacking the distinctive Southern drawl. Moss offers to pay one of the men 500 dollars for his coat. Following an exchange of distrustful remarks, they agree. Later, after having collapsed on a staircase in Mexico, Moss is woken up by the music of a mariachi group playing only a few feet away from him
No Country for Old Men - Border Scene
No Country for Old Men - The 'United States Border Station
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