The loss of cultural artifacts through war or through disaster has occurred throughout the world and certainly there is a lot of material available about this from the World Wars. Some years ago I joined what was really a museum listserv and there an example was raised about a pacific island nation that, through both disaster and economic hardship, was battling to preserve it's cultural heritage (even at the level of being able to man the museum more than a day a week and have a phone). The tsunami may have led to problems also in this area.
The issue of e-bay is really economic greed/desire (because it's not always greed) vs heritage retainment and preservation. It can also be about the 'average joe and judy' knowing how to decipher the value of an object they may locate in granny's attic and so on.
I would also add that some countries are now asking for their national items to be returned to them (items lost either via war pillage or via being stolen in war times etc and passed onto collectors in other countries). This is even a forensic issue at the human cadaver level where the body parts of indigenous peoples et al have found their way into museum collections internationally (and communities are now asking for their return).
yes, I recall the spielberg related case..interesting