If you are reading your credit card numbers off to someone on the phone, do just that. Don’t say “October” when it clearly reads 10 on your card. Does it seem reasonable that there’s an “October” button on the other end? Chances are more than likely that the person listening to you knows to change it to 10, but why complicate things? The other person is typing 16 numbers that you’re reading them, just give them the expiration date in kind.
When reading a long sequence of numbers, just read the digits. Especially when there is a long sequence that needs to be recorded. One, six. Is very clear. Sixteen, is less clear, because the first syllable implies a six, and then modifies it to a one. This applies to fourteen, sixteen, seventeen, eighteen, and nineteen. There is no good reason for ambiguity in this manner.
I agree that these are trivial manners in the grand scheme of things, but I do not agree that they are worthless. Small things cannot be overlokked if we as a nation are expected to be able to compete in the global market. Little things add up.