How to behave on the Tokyo subway

Mark blogged some etiquette posters from a Japanese subway system back in December. And they're fine, as far as they go. They just don't go far enough. They don't liken seat hogs to Space Invaders or, most imaginatively, Hitler. They don't invoke The Last Supper to beg riders not to forget their umbrellas. (The sorrowful look on Jesus's face as he contemplates the mass of lost umbrellas is worth the price of admission.) And they don't put a Scotch on the rocks in Santa Claus's hands to illustrate — you know what? I have no idea what it illustrates. Does it matter?