Customers are gods, as a saying goes in Japan, where staffers press buttons for shoppers in department store elevators and hotel porters line up to bow to guests.

While Japan is revered for this hospitality, or omotenashi, all that bowing and scraping may be sapping productivity. So much so that the nation has ranked lowest of the Group of Seven nations by that measure for nearly 30 years.

With Japan facing a labor shortage as the population ages — the jobless rate is at its lowest since the late 1990s and projected to fall further — Prime Minister Shinzo Abe wants to more than double productivity growth in the service sector by 2020. He is targeting the service sector, which makes up about 70 percent of the world's third-biggest economy, and has failed to embrace technology like Japan's manufacturers.