Those who are capable of making awesome changes/modifications will continue to do so while those who are incapable will continue to crib that it is unethical.
Blanket statements like "compositing is not photography" don't hold up in all cases. HDR photos are composites of several shots. Are they not photography, simply because they were combined after the fact? You could have achieved the same thing if you used a grad-ND filter, so does using a filter mean the photo is 'not photography'? What difference does it make if you did the composite before the click or after?
Also, compositing doesn't always mean introducing something that wasn't there. The photo below is 3 different exposures, composited together in Photoshop. Point to the element that wasn't actually there.