Only about a tenth of omurice is tagged omelet. I also take issue with omelets and omurice not looking different.
...however, I cannot disagree with the implication because the first 50 results of omelet -omurice -tamagoyaki have a grand total of 14 images that are not untagged omurice. 36/50 are omurice. 5 of them are tamagoyaki. Of the remaining nine, only one is not a mistag (fried eggs, no eggs, one is spaghetti). And even then that last one is debatable.
Randomly going through the pages nets me more omurice than anything else.
Edit: I've gone through omelet -omurice -tamagoyaki and tagged all the omurice and tamagoyaki. THen I fixed all the fried eggs and whatnot. It's down to a grand total of 28 images.