Well they won't be putting in the oven until ready to bake and different colors can be baked at same time as they are applied in a different area---Its also very easy for them to change colors as it isn't liquid---oven $ is where the costs can be saved and thats where the best guys have maybe a triple oven to allow for preheating in one section while baking in another while emptying/filling the third section( sort of like a shell game)
In recent decades I have when to powder coat or SS with shiny stuff fabbed out of SS and polished