Japanese business travelers often stay at Business hotels which offer a somewhat less expensive stay. The hotels are generally located close to railway stations which makes for a convenient stay but the rooms can be quite small and usually without room service and few amenities in the room. You will find vending machines in the hall way where you can by snacks and drinks. Usually there will also be a restaurants in the hotel or close to the hotel.
As Wikipedia points out:
When reserving any Japanese accommodations, bear in mind that many smaller operations may hesitate to accept foreigners, fearing language difficulties or other cultural misunderstandings. This is to some extent institutionalized: large travel agency databases note which (few) hotels are prepared to handle foreigners, and they may tell you that all lodgings are booked if only these are full! Instead of calling up in English, you may find it better to get a Japanese acquaintance or local tourist office to make the booking for you. Alternatively, for cheap Internet rates, Rakuten’s English search tool is an invaluable utility. Note that prices are almost always given per person not per room. Otherwise you may have a rather unpleasant shock when your party of five tries to check out….