It isn't that. Or at least not only that. They are pragmatic nation. They are considering who and why would want to use the map, and then tailor it to meet the needs of an audience.
I am not sure about other countries but European maps are always oriented for north. Which works fine when you read them in book, but not necessarily when you are looking at big guide map on the street. Yes, sure, this map may show red "you are here" mark, but it is still difficult to find out your way as a map itself is always oriented to north, while you may not be.
Japanese street maps are oriented on you (most of them). When you're standing in front of it - "up" on map always means "go forward". Which might be confusing at the beginning, if you came from Europe. But the more you look at them, the more easy it is to find your way.
Hollywood Studios in Disney World had a park map where the entrance to the park wasn't at the bottom, I found it really disorienting, I think due to the effect you mentioned, I naturally want to walk 'up' to 'go forward' through the map
I am not sure about other countries but European maps are always oriented for north. Which works fine when you read them in book, but not necessarily when you are looking at big guide map on the street. Yes, sure, this map may show red "you are here" mark, but it is still difficult to find out your way as a map itself is always oriented to north, while you may not be.
Japanese street maps are oriented on you (most of them). When you're standing in front of it - "up" on map always means "go forward". Which might be confusing at the beginning, if you came from Europe. But the more you look at them, the more easy it is to find your way.