But if any person digs for artefacts,they may accidently damage them.
plus the artefacts/items may end in private collections,never to be seen.
That is true for the truly ancient sites and bodies. However In this case WWII artifacts are pretty durable, and only 60 years in the ground the remains would still be in good shape. But I get what you are saying. The error would be their lack of cataloging and complete disregard of the site for historical purposes. So many men went missing on all sides.
A few years ago a couple of Americans were found STILL in their foxhole in the Hurtgen Forest where they died during WWII and one was from the town I lived in. It was pretty amazing. Full military burial 66 years after he died.
Oddly enough they were found by German Soldiers in 2008 sweeping for mines left over from WWII.
I see nothing wrong with anthropologists digging up ancient stuff to research whatever they want to about whatever they find as long as they have the appropriate permissions. If they didn't we wouldn't know dickall about anything human from before recorded history.
Native Americans are pretty tough when it comes to this. The remains could be 4000 years old and they would pretty much say tough sh**... leave them be.