Either way, I'd guess those pans are the survivors of a larger "stash", much of which made trips over Berlin and Tokyo. Look how battered a lot of them are, and the insides as well. They've been well used and well loved.

I would bet those cooks knew their business--they had to compete both with the excellent cooks on dining cars, and also the excellent restaurants train passengers knew were in the Loop.

Sad to say, Union Station is all fast food now. It's still a beautiful building--my wife and I have gone there a few times, including on our honeymoon--but it's a shell of what it used to be.

They're fashioned out of copper.