Marunouchi is THE office district of Tokyo where many of the big companies have headquarters, so prices are geared to well to do salary men/ managers and the infamous Marunouchi OL (Office Ladies)... Of course Tokyo is expensive, but there are bargains to be found in the lunch specials and cheap souvenirs at the 100 yen shops. I'm on the West side of town, so I tend to frequent the Shibuya and Omote-Sando Citibanks.