MacGuffins can happen in real life.
The world as we know it would be turned inside out. Countries overthrown. Entire cultural history tossed aside. Dogs and cats sleeping together. Cubs wining the Series. Stuff like that.
The post "Jim Groom’s Career MacGuffin" was originally yanked out of the teeth of a rabid chicken at CogDogBlog (http://cogdogblog.com/2011/09/jim-grooms-career-macguffin/) on September 23, 2011.