For all of those who believe in religion?

How do you people (non-atheists) justify that some of the smartest people in the history of time were atheist? such as: Albert Einstein, Ben Franklin, Carl Sagen, Ernest Hemmingway, Frank Zappa, Sigmund Freud, Thomas Edison, David Chalmers, Karl Marx, Bruce Lee, Warren Buffet, Bill Gates, George Soros, Constantine Fitzgibbon, Lance Armstrong, Richard Dawkins, Albert Ellis, Ivan Pavlov, Isaac Asimov, Douglas Adams, Thomas Paine. The list goes on and on. Whats your answer?