Every Olympic sport has an annual championship in different cities at different times in Olympic off years. Having everyone together in one place at one time is what makes the Olympics special. Special for the athletes, live spectators & host city alike. The more the Olympics are spread out physically, the less special it is for the most people.
On the other hand, I know this is a little naive since most of the money revolves around TV rights. Also, as a TV spectator, 24 hour live coverage (like the Watanabe is suggesting in the article) of the Olympics sounds pretty cool. I wonder if the TV networks would like this. It probably solves a lot of the logistical issues host cities have been having as well. This also avoids the worst outcome of coming to a point where only a few host cities, like LA and Paris, can reasonably meet all the IOC's demands games after games.