This is an age old battle about the use of formal vs everyday use. And usually the people of the "next generation" are the ones who change things around. I'm sure someone from the 1800's wouldn't begin to recognize the way we talk today as the American English they knew.
I remember a comment from a friend when I was in Australia a long time ago about how the young people were so impolite in the shops because they said 'Ta' instead of Thank You. The last time she was here visiting me she was saying 'Ta' all over the place. It just goes to show you how we get use to things.