I read somewhere that the reason for the additional letters in English (UK) (like favourite and programme) are because typers back then were paid by the line so adding in additional letters to the word (that didn't change its pronunciation) got them more money.
Then, Miriam Webster when making his dictionary sought to remove the added letters that didn't need to be there. Thus the difference between the two 'versions' of English that we have.
Thought, it was a bit of interesting history...
In the end, English as a whole is pretty messed up language and one of (if not the) most difficult languages to learn for spelling, pronunciation, and grammar. We have so many 'rules' that we don't follow its crazy.