Japan due to shear number uses wide bodies domestically. They had special 747-400 with no winglets. As with the short flights they didn't curise long enough to get a benefit of improved fuel burn of the winglets to counter act the additional mass they had to carry to altitude.
When slots become an issue and airport can handle longer dwell times at gates, wide bodies start to get used as have to move the people. This isn't an issue in NZ yet. Would add more domestic gates and up the frequency to every 15-20 at peak.