There was a very interesting thread a few years ago after the Oriskany was sunk off of Pensacola, Florida and someone (illegally) took major material and bragged about it online. It was interesting because the thread broke into a flame war between two very opposite sides of the issue. One side had a view similar to the OP's--wreck artifacts are there for the viewing enjoyment of all divers, and they should be left as intact as possible so that everyone can enjoy them. The other side believed that wreck artifacts were there for the taking, and all praise goes to the one who takes them and accumulates such souvenirs--they were just going to rust away in a few decades anyway, so why not take them and enjoy them on land?
The diver who took the Oriskany artifacts and openly bragged about it was clearly stunned to learn that the other side even existed. His total previous experience had been with divers who were unabashedly in the looter camp, and he did not realize preservationists existed.
What struck me about the thread was that neither side could see the point of the other--at all. As a preservationist myself, the arguments of the looting contingent seemed foolish to me, but the arguments of the preservationists clearly seemed foolish to the looters.
So, as sad as it is that this looting occurred, I doubt that posting a thread about it here on ScubaBoard will have any real effect. Even if the person who took the stuff reads it, his or her attitude would likely be, "So what?" Others in the school of thought will wonder if there is anything else there for the taking. I imagine some of them will be offended by my use of the word "looting' to describe that activity. People who regularly carry hammers and chisels as normal wreck diving equipment and even talk about the best way to carry them on their web sites believe it is a totally legitimate activity.