If you're looking at a map that's fixed to a wall or a couple of posts in the ground, then the top of the map is usually the direction you're facing to read it. (Even if the map is underground). It must increase the cost of planning and printing street maps ... but the orientation of those maps isn't just random - there is an organizing principle, of sorts.
When it comes to portable, paper, maps ... omst Japanese people do that thing of twisting them round and round until they can see it's pointed the way they're pointing - as if the world needs to align itself with them (or as if it's impossible to imagine a direction other than forwards when looking at a piece of paper). When I see someone doing that with a map, (or worse, a nautical chart), my heart sinks.
Having said that, the old maps of Edo with all the names of the daimyo around the castle legible only when you walk around (or twist the enormous map, god forbid) to that part of the map ... those are pretty cool.