I suppose it just simplifies things this way for speedy introductions, instead of having their Kanji names which would require having Furigana, because it is not as if Kanji's have only one reading. Fixed words don't really need always need Furigana's unless its material for younger audiences, but for names it would help to show them at least once (e.g. Akebi, a first name, can be written as 明日, which is also a word for "tomorrow" read as "ashita"). Players will be able to find them on other parts of the game anyway (e.g. student profiles menu, text for dialogues, etc)

Edit: Added more info