It's just marketing guys, think of it as political pandering, more population, more patriotic population(emotional attachment), etc. I'm sure we all agree that America is more linguistically and geographically "challenged"(market potential) than the Brits yeah?.... sooo market where the market is. As for Brazil, that's a sheer population decision. They tried to shove Spain's version of spanish audio translation into the latin american portion of the new world (the thinking I guess was since america loves the british accent in movies... but it flopped.... now Hollywood/movie industry recruits voices from Mexico and other latam countries.