You can eat cheap in small restaurant, the majority of them family-run business.
Menus offer a good variety; one just has to point something at random. Service is fast. We can order a bowl of plain rice or noodles, a dish dressed with vegetables, meat, eggs in sauce … (Chinese sauces, found almost over all the dishes, give them their consistence and the bulk of their taste. Also, it makes say to the other neighboring people, such Japanese, that “ Chinese food is oily ” .)
People go so frequently to these restaurants that is common use to take away the rest of the food to be finished at home.