What does anything matter. If you deal with someone else at least one of you needs to learn the others systems. You and your neighbor probably speak the same language so it is easy, but the more differences the more there is to learn. You can choose to not deal with people in the US who only know US systems, or you can work with them by learning. I have no idea what your motivations are, but whatever they are they becomes your reasons to do or not do something.