In this case, from Jeff Peterson…
My confidence in the veracity of Mickey Rooney's anecdotes has been slipping since he started telling everyone that Walt Disney named his mouse after little Mickey McGuire. It's a cute story, but the chronology and geography don't align with historical facts. However, to be fair, it wasn't all fabrication since there once lived a man named Walt Disney, and the mouse named Mickey still resides in Anaheim (and other locations).
Regarding Rooney's assertion that Boys Town was filmed in two weeks, it is hard to believe that the world's Number 1 Star (1939-41) would intentionally deceive anyone. Checking the facts in Variety, Boys Town started filming at MGM on June 6, 1938; completed principal photography by August 9, 1938; and was released on September 9, 1938. However, the company filmed on location in Nebraska for two weeks in late June and early July, so perhaps that was the period of time which Mr. Rooney recollects.
Or maybe he was thinking of the 1941 sequel, Men of Boys Town, or the 1946 Disney remake, Boys of Mice Town, starring Mickey Rooney and Mickey Mouse. More recently, in 1989, Ted Turner had Boys Town colorized, which probably took about two weeks. Or, maybe, for the 1991 documentary, Something A Little Less Serious, Mickey Rooney sat down and talked about Boys Town for two weeks.
Anyway, getting back to It's a Mad, Mad, Mad, Mad World, personally, I thought the supermarket scene with Mickey Rooney and Buddy Ebsen was the funniest part of the film. But it would have been funnier if more food had been destroyed. And it would be hilarious with Will Ferrell and Melissa McCarthy speaking nothing but ad-libbed curse words.
I once heard Mr. Rooney give a talk in which he told his oft-told tale of how Walt Disney told him, "I'm naming my new mouse character after you." Giving Mick every possible doubt, it's possible that Disney, having already decided his mouse would be Mickey, told the kid that to give him a thrill. Yeah, I don't really believe it either but it is possible. Other things Rooney says are not…but still, I feel sorry for the guy. He's 93 and he ain't working much. He's separated from his eighth (eighth!) wife. He recently went through a messy legal situation which included him testifying before a special U.S. Senate committee on elder abuse about how family members had allegedly stolen money from him.
As I was listening to him the other night at the theater, I started thinking of a joke. It's something about a guy who befriends a magic frog and the frog grants him a wish. I haven't figured out the middle part yet but the punchline goes something like this: "The good news is that you're going to get your wish and become a movie star. The bad news is that you're going to be Mickey Rooney."