[shiroiushi]

AFAIK, there's nothing legally preventing stores from charging more at more-convenient locations. However, in practice I don't normally see it. I believe (not sure) that major convenience store chains, for instance, have fixed prices for the same reason Walmart does: it's too much trouble to track different prices at different locations. As for restaurants and stuff like that, there's usually a lot of competition, so I just don't normally see obviously-higher prices at locations in stations or airports. Of course, some things are obviously more expensive than alternatives: milk at a convenience store is more expensive than almost any grocery store, for instance, though usually not by much. But for whatever reason, I just don't see such obviously and ridiculously jacked-up prices as I see, for instance, in American airports.