The tickets may be half the price, but there is the nagging issue of flying to Tokyo. The food is also not cheap and it's worse. I've eaten everywhere and there is almost nothing on the level of Sanaa, Topolinos, California Grill, or even Teppan Edo. Tokyo outside of Disney has some of the best food in the world, but the park food in Tokyo isn't good or cheap.
Again, the Japanese people have a lot to do with the cleanliness and efficiency of the parks. However, I've found Tokyo Disney to be way too crowded and small. There isn't a single ride in Tokyo I prefer to its counterpart in WDW besides the ones it has that WDW doesn't, such as Snow White.