Train stations are no exception. Some smaller train stations do not even have an elevator. I have found out that public buildings less than five stories tall are not required to be wheelchair accessible or to have an elevator.
I spent a stupidly long amount of time looking for an elevator and the train station today. Because it took so long to find one I was in a hurry. In my haste, I got on the wrong train for the first time since living in Japan. Unfortunately, I was also not paying attention and it took me a long time to realize I was on the wrong train. Whoops!