There was a great Astro City issue, featuring a comic book company that used "real" heroes for their material. Eventually the head editor (sort of a Funky Flashman-type) was threatened by heroes and beaten into a full-body cast by villains, and decided that the audiences wanted stories about cosmic heroes and villains, guys so powerful that "they wouldn't give a rat's ass about earth."
The next day, the main character (a writer) shows up to work, only to find the whole building inexplicably vaporized.