Whoa, whoa, whoa. America has non-superhero comics, of course - the Sandman series, Y: The Last Man, Preacher, The Walking Dead, American Vampire, etc.
...but Marvel Comics is superheros. Marvel is owned by Disney, and Disney has a huge marketing budget. DC Comics is superheros...owned by Warner Brothers.
EDIT: yeah...none of those that I mentioned are remotely for kids. Hmmm.