Before panchromatic film photographers made composite images by printing in clouds in an otherwise white sky. Different landscape shots would all have exactly the same clouds
For me personally adding elements that were never there doesn't interest me. However, all images are processed after clicking the shutter release:
- automatically by the camera using a selected picture style
- automatically by the RAW converter when you first import it into DPP , ACR, whatever
- if you ever shot film ALL images sent to a print lab were manipulated to get the color, contrast and brightness "correct"
- if you send your digital files to a print lab ALL of them get corrected for color, contrast and brightness unless you have the option to tell them not to
Sometimes you need to post process because of exposure errors, but often it's to be able to create something that better represents the scene you visualized or to create a mood. Ansel Adams, Yousuf Karsh and others all manipulated their images using dodging, burning, unsharp masks, vignettes, paper contrast and textures to create powerful images that weren't necessarily a perfect representation of the scene.
To me it's difficult to make a great photograph unless the basics are there (good light, exposure and scene), but I've yet to see a great photograph straight out of the camera and processed as "camera neutral". But who am I to judge? I remember when "Red Stripe on White Canvas" was considered great art ... or maybe it still is?