He was from there, before that rogue hot-air balloon landed him in the Emerald City. In the movie, he went back to Kansas the same way - leaving Dorothy to get home using the little-known transportation method, shoe-clicking.
Dorothy must have told the Wizard that folks like to eat at diners; and when they do, they enjoy home cooking. The Wizard asked why they didn't just eat at home if they enjoyed home cooking. Dorothy said, what did he know, he had minions bringing him meals back in the Emerald City and had no idea what it was like for her and Auntie Em, whipping up meal after meal.
So now he's running the Emerald City Diner and pushing Heinz soups on everyone. I guess the kitchen minions didn't fit in the hot air balloon and this is the best he can do.
|Tin Man in 1903 stage production of Oz|