Three kinds of Americans

(1) Those who talk loudly in public (on the street, in stores, coffee-houses, libraries, museums, parks...) because they don't know better

(2) Those who talk loud because they derive an overweening sense of their own self-importance (and don't give a sh*# if it bothers others). 

(3) Those who don't (and eschew doing whenever possible).
There's a latent Brit in many of us Yanks.