Maybe it's easier for development if they're individual? Who knows? As a user the number of files needed for an application is irrelevant. Maybe the dictionary

Maybe it's easier for development if they're individual? Who knows? As a user the number of files needed for an application is irrelevant. Maybe the dictionary that Word uses for the spellchecker doesn't need to be a part of the executable, so if they want to update it, they can replace just that file and they don't have to make you download the entire program again?