It is also about locations.
If a British author sets their story in either Leeds, Norfolk, Glasgow, Leicestershire, Stoke or Devon, the British reader will already know in their mind the culture of that region and the people who live there, which adds another layer to the story.
I assume that when an American author also chooses their location for a story it is done for a specific cultural reason, that a Brit probably won't understand.
However I suppose if a story starts with a teenage girl from California moving to a school in Texas, most Brits would guess she is in for "an interesting time".
