One of the great invention of Japanese...might be sushi-go-round restaurant. I personally don't find any reason that sushi should go round on table, but it is indeed popular sushi bar not only in Japan but also in other countries. Maybe the answer is just fun!
Exterior of "Ganso sushi"
Sushis are rolling on conveyor belt
Or another reason is that we can eat sushi at reasonable price in sushi-go-round restaurant(of course, the quality is proportional to the price). Also, it enables us to eat sushi lightly and quick whenever we want. Recently, I went to a restaurant named "Ganso-sushi(元祖寿司)" in Asakusa(浅草) with friends. All self-service system is applied to this kind of restaurant. We made tea by by ourselves and we can pick up any sushi from the conveyor-belt. If there is no favorite sushi, we can also directly order to sushi cooks. As for the taste, tuna was not so bad, but others were not good enough. In particular, the rice was still warm, which harms the taste of fish. The sushi rice must be cold. Accordingly, my rating is not high, 1.5 out of 5. Even so, I enjoyed the atmosphere of sushi-go-round restaurant after so long. Gochiso-samadeshita!