I've read many posts now and talked to several people who are into digital photography but refuse to make use of image manipulation software. But so far I haven't heard one good reason for this. Everytime I ask people about it all I get is "religious" answers about how it is "evil" to retouch your photos and that only what came out of the camera is truly "pure". Are there any real valid reasons for not using image manipulation programs?

I understand that trying to get the perfect shot on the spot and not relying on software will ultimately make you a better photographer, but no manipulation whatsoever??? To me this sounds like if someone has a six string guitar and only plays one string because the others are somehow unpure. Or am I wrong about this? Is image manipulation an integral part of the digital photography work process or something that only blasphemers do?