While I don't think any museum 'professional' or serious scientist should
 encourage Pot Hunters.  There is no doubt they destroy or at least badly
 damage the sites they attack.  Realistically, those folks do play an important
 role is promoting preservation as well.  I suspect that many of the people in
 the effort to preserve American Civil War battlefields from commerical
 development started out collecting Minne balls.  On private land, if pot
 hunters did not hunt artifacts-many sites/artifacts would just be lost totally
 due to development and the like.  Perhaps half a loaf (the artifacts) is
 better than no loaf at all.  In addition, I would ask, do common artifacts
 have more meaning  displayed close to where there were found or in a drawer in
 a far off institution?  Is a flint point better shown on the wall of the farm
 where is was found or buried in a collection where it will never be seen?