I am one who thought Japan would be very expensive before my first visit. I found it merely expensive, in the way that New York is an expensive city. Certainly if you're trying to do the nicer, higher-end things in Japan, it is an expensive or very expensive place to visit. But plenty of things are not totally out of control expense-wise. The Tokyo subway, for example, is not expensive at all, and you can get plenty of good meals in perfectly acceptable restaurants for roughly what you'd pay in other major world cities.
You want to talk about expensive cities for visitors: try some of the European hotspots like Paris and Venice. Yikes. When Mr. Megatop and I talk about where we want to go next, discussion of Europe typically ends with "it's so expensive." Discussion of Japan typically runs something like, "When should we go back and where should we go while there?"
Looking forward to our next visit, Christmas upcoming, because we're among those who fell in love with Japan on our first visit.