Originally Posted by s0ssos

You also have trains with a mandatory seat reservation. And yet you have another fee, that is not optional. Why not just include it, because all fares on that train have seat reservations?

I've only used JR pass, where you just pay what they tell you (so I have no idea what I am paying for), but wondering if you purchase a ticket whether the agent could ever get it wrong, and you be denied boarding because you haven't paid one of the mandatory but not included fees? Though I feel in Japan they would be nice about it, and their agents shouldn't mess it up.
Like the thread about someone denied boarding cause nobody at AA bothered to figure out they needed to pay taxes for their infant.