I hate seeing a wreck disturbed but it happens every day due to currents, storms, natural deterioration, and anchors tearing a wreck apart. I knew a diver that I did not like at all that lifted a large anchor from a wreck and placed it in his yard. If I turned him in it would have given ammunition to those that wished to ban divers from all wrecks. I learned to appreciate the wreck without the anchor.
I understand the laws..... I just have a hard time seeing the difference between a private person recovering an item, a for profit company doing the same thing, and a museum. It seems to me that all 3 are destroying the underwater archealogical site. One is doing it in the name of science, one is doing it for pure profit, and the other for a souvenir that will eventually wind up in a collection (public or private).
I agree that we shouldn't all descend with prybars and lift bags... there wouldn't be much left if we did. However, at the same time, a commercial or quasi-commercial organization doing the same thing isn't any better. Most of the high-profile cases I know of are simply sour grapes. In one case a Spanish ship was found by a company and Spain suddenly wanted it back. Um, excuse me, but if you haven't missed it for 300 years you probably don't need it. And wait a second, but the "treasure" was stolen from the native people in the first place and I'm sure that their claim to it supercedes Spains claims. One atrocity doesn't make another justified.
If we were to take out of context for a second that the items are historical in significance.... they would be considered pollution. If I wanted to go and drop an iron anchor in the bay I would be required to immediately remove it for fear of the damage it would do.
While I respect that in most wrecks someone has died there..... I don't see a rush to stuff the Egyptian treasure back in the pyramids... and that was an actual tomb. Again, if we are going to say that it's sacred than nobody should be taking anything up. Just because you work at a non-profit that pays it's director $250K/yr or some other rediculous sum of money doesn't exempt you from the fact that you are still taking items from a grave.
After all, who knows... archeaology might advance in 50 years to the point where they can do a better job of recovering items and restoring them. So perhaps we should just leave it the heck alone and take only pictures.
I think this is really a shades of gray issue. My personal opinion is that it is wrong to dive with the intent of plundering a wreck. Who the heck wants a anchor in their yard anyway? Unless you want the Tacky Yard of the Month Award. Just bear in mind that you are stealing the experience from everyone who won't see the item. Ask yourself what the wreck would have been like if the item you are about to steal was missing.
As for museums and professional thieves..... if the general public wants to see the wreck they can:
a) Watch TV
b) Learn to dive
When we plunder every wreck for it's artifacts and interesting tidbits it leaves a pretty boring dive site for the rest of us.