Maybe the artifacts should stay in the ground for no one to see? Or buried in museum basements where no one but researchers can enjoy the material culture of long-dead peoples?

Important private collections are almost always published and these collectors spearhead (and pay for) most of the research into the artifacts. Without private collectors the public would remain wholly ignorant of whatever it was being collected.

The vast, vast majority of museum holdings are never displayed to the public so instead of being kept in permanent obscurity these artifacts would better serve the public being private collections.