Anyway, the most interesting section on the page is "TRPG中における飲食", or "Food and drink in TRPGs". Here's a rough translation:
In TRPGs, food and drink, focusing around snacks, have a special significance. Having food and drink while playing the game with friends lets you enjoy the flavours while livening up the conversation, and is another element of the fun involved. In Mishio Fukuzawa's "New Fortune Quest Replay" [whatever that is], snacks and drinks are listed in the book as "necessary items". Other TRPG books don't go so far as to say they are necessary, but many recommend them.
In replay books [basically a sort of novelization of a game session - yes, really] there is not usually a commentary, so there is also no commentary on snacks, but in the Sword World replay "[Title Untranslatable Because I Can't Be Arsed, it's Something Like 'Rhapsody of the Marauders']", there is some out-of-character commentary by the players regarding snacks, such as "I'm going out to get some juice", or "I want some ramen".
TRPGs are played with a number of people, and take a few hours, so food and drink is also used to alleviate the hard work. It is desirable for all participants, including the GM, to prepare and manage the food. If this is not observed, the other participants will likely judge the offender unfavourably and be unsatisfied. It is usual for all the individual participants to to bring stuff, because expecting one person to bear the burden of providing food and drink is rather onerous.
It is important to watch out during play that food and drink do not become a hindrance, especially when using a board or maps and so on. For instance, drink might be spilled and ruin a character sheet. It can also get on ones hands and make them smell. When the game approaches a meal time, it is usual to have a break for a while and then start again afterwards.
During online sessions there is no chance the other players will take your snacks, so you can enjoy them in comfort. However, you also can't take other players' snacks either.
Those Japanese, eh?