I was always curious about Jack Benny wearing a derby in his cameo. He wasn't know for wearing any kind of hat, much less a derby. I recently read that his cameo was originally intended for Stan Laurel of Laurel and Hardy fame.
Whether true or not, that's the way I've always heard it. It's a double driving the car in the Yucca Valley location long shot, and Benny's closeup was done subsequently on a soundstage (before a rear-screen projection).
Normally, casting matters would be long-settled before a film, especially such a big, lavish one, goes into production, but perhaps Kramer and company were still hopeful of enticing Laurel's participation at that late stage, however unlikely that would ordinarily be. And somewhere along the line, someone may have pointed out, "Well look, whoever we get, whether it's Laurel or somebody else, all we have to do is put him in a dark suit and derby to match the location shot."
It's interesting to consider what might have been intended for Stan; after Mrs. Marcus' rude refusal of any assistance, perhaps he would have broken into his famous cry (which Mr. Laurel had long since come to hate doing), whimpered, "Well I was only trying to help" (in place of Benny's indignant, "Well!"), and doffed the derby momentarily to do his trademark hair mussing before replacing it and driving off (to a few notes of "The Cuckoos" rather than Benny's "Love In Bloom").
That's a great "what if." I'd never heard before that Laurel had been offered this cameo. How awesome would that have been? Benny's okay, but Stan Laurel was a comedy god.
The story on Stan Laurel was that he was offered this role, but the year before Oliver Hardy had died. He had said that he would never act in anything once his partner was gone. He kept his word and never did. Kinda sad!