I think if you order a misu soup, eat a meat entry, all of the noodles/rice, and desert it is more than enough food for any meal and feeling the need for more after that is just being a piggy. I mean I had a half a plate covered in steak and chicken, the other half noodles & veggies, and a separatebowl of rice, plus cake at the end, if you are on dining plan. I only had a full breakfast, and an ice cream sandwich around lunch, so I went in with a full appetite and was happy. (and I'm a 230 pound guy who loves to eat!)
That said, the world showcase has no shortage of other snackys abound if somebody is still hungry. However, if someone can't handle eating the rice/noodles/& soup because they are strictly meat & potatoes they will probably be hungry but then you probably should stick to America/UK/Canada for your country dining options.