I collect military buttons, and I often notice buttons on eBay which are claimed to have been dug from historical battle sites. Buttons alleged to have been dug at well known battlefields such as Balaclava, and US Independence and Civil War sites such as Saratoga command a high premium. Personally these don't interest me, first because I only collect buttons in as good as condition as possible and secondly it is difficult to prove where these items have come from. What I am saying is that this is nothing new, and frankly unless personally identifiable items from known grave sites are being sold I see little to object to.