MarkUK:
I think you have your figures all wrong. I think it is the minority of divers who feel it is okay to go down and molest marine life, moving stuff into better positions for photos, etc.
Although I don't think it is a good idea in general to touch marine life, as a videographer and educator I am one who will touch and move certain species to get a better shot, or even use contact to elicit certain behaviors in certain species so I can film them. If I encounter a rare or unidentified species, I will try to position it in a way that allows me to capture the key features that might help more knowledgeable scientists to ID it.
I am almost always selective in what species I will touch. These are ones that I know will not be significantly impaired by my touch. Ones I am unsure of, I almost always leave alone.
I faced this issue recently with a sea cucumber I've seen 7 times but hadn't yet identified. I repositioned several of the individuals to get good footage of what might be diagnostic features. In repositioning one, it started to eviscerate (expel material from its anus). My touch was gentle so I was quite surprised.
I inspected the eviscerate and quickly realized it was not the digestive tract as some sea cucumbers will expel. I induced a few of the others I encountered on that dive to eviscerate so I could get good film to use in my educational videos.
Was it proper to do so? Possibly not. I made the decision to go ahead this time for scientific and educational reasons. Will I do it again with this species? No, I have sufficient footage to ID it and present evisceration as a defense mechanism. No need to do it again.
I have frequently railed about those divers who kill sea urchins so they can feed the fish (especially when they do so in our dive park which we try to treat as a protected area until it officially receives that designation by the State). Sea urchins are not a problem in most parts of Catalina so there is no ecosystem health issue to "justify" killing them to attract fish. Knocking two stones together often accomplishes the same goal without hurting anything (except, perhaps, the encrusters on the two stones!).