Well now they could set up a kiosk that looks like a giant DS with a touch menu on the bottom screen and video display up on the top screen.
edit: And what I meant was that lots of people, like parents, will probably look for whats popular and get that for their kid or as a gift for whoever they are buying it for, and if some game maker can make sure their game makes that "popular" 300k+ sales list on the kiosk, it could increase that PoP sales and make a small advertising budget worth the cost.
I'm sure they will have all the games listed, but who wants to sort through that incredibly long list when you don't know what you're looking for?