In recent years, as cultural values have gradually shifted towards favouring restitution, incompatibilities between the views of archaeologists & the museum / art dealing community have been accentuated.
While Museums & art dealers value pieces as a part of a collection (ideally their own), archaeologists attach more value to the study of the artefacts within their original context.
This conflict is something that might be more publicly debates in the USA at present, but which is equally applicable to the museums in many other countries as well.

From:
New York Sun

Collecting vs. Cultural Heritage
Museums
By KATE TAYLOR
November 17, 2006

In two different parts of town last night, two very different voices in the debate over museums and antiquities made their arguments heard. Uptown at the Metropolitan Museum, the Met’s director, Philippe de Montebello, delivered to a rapt audience an impassioned defense of museums continuing to collect antiquities –– while, downtown, Peter Watson, the author of “The Medici Conspiracy: The Illicit Journey of Looted Antiquities — From Italy’s Tomb Raiders to the World’s Greatest Museums,” spoke to a group at the Chelsea Art Museum about the responsibility of museums not to contribute to the illegal trade in antiquities. After his talk, Mr. Watson was honored at the gala of Saving Antiquities For Everyone (SAFE), a nonprofit organization dedicated to preserving cultural heritage.

Mr. Watson spoke primarily about his book, which is named for the Italian dealer Giacomo Medici, who was convicted in 2004 on charges of antiquities trafficking. He predicted that the recent agreements between the Met and the Museum of Fine Arts in Boston and the Italian government, which involve returning disputed objects to Italy in exchange for loans of comparable ones, will not end the battle over cultural property. The MFA, for instance, has agreed to return only 15 objects, but Mr. Watson said that in his research he discovered nearly a hundred with hazy provenance in the museum’s collection. He also predicted that other countries, including Greece and India, will start bringing cases against museums.

In general, Mr. Watson implied that museums are dragging their feet on this issue and still failing to do due diligence on the objects in their collections.

Uptown, Mr. de Montebello’s lecture was ostensibly a history of collecting antiquities, from the time of their creation to the present, but it had a quite explicit agenda. This was to encourage the audience not to blindly accept the Met’s agreement with the Italian government as a sign of enlightened “progress,” but to look critically at the debate between the values of cosmopolitanism and cultural identity, and to recognize that encyclopedic museums like the Met, the Louvre, and the British Museum would not exist if objects had not continually moved around the world for centuries.

His history began in classical times, when victors in wars often took home works of art from the defeated as trophies. (This continued into the 19th century, when Napoleon kidnapped the four bronze horses on the façade of San Marco in Venice and paraded them around Paris.)

Mr. de Montebello continued through the 19th century, when the English, French, and Germans sponsored archeological digs in the Mediterranean region and shipped what they dug up back to their own capitals ––creating those encyclopedic museums –– with little complaint from the source countries, Mr. de Montebello said. Eventually, a system of partage, whereby the sponsor and source countries shared the finds, developed.

In the 20th century, with the rise of nationalism, source countries rescinded partage and passed cultural property laws. Because these were generally disregarded, a black market sprang up, and archeological sites were looted and objects destroyed. In 1970, UNESCO adopted its convention on cultural property, urging compliance with these laws.

As he has in the past, Mr. de Montebello ridiculed archeologists who assert that an object is “meaningless”if the location where it was taken from the ground (its “find spot”) is unknown. To convey that he was not attacking archeologists generally, he also cited several archeologists and scholars, include Lawrence Stager, a professor in the department of Near Eastern Languages and Civilizations at Harvard, who themselves oppose the position of the Archeological Institute of America — that its journals will not publish scholarly announcements or presentations of objects of unclear provenance.

Most important, he defended the right –– and necessity –– of museums to continue to collect. Even long-term loans, he said, “cannot be a substitute for a responsible acquisitions program,” because curators can’t always be dependent on lenders in creating their exhibits. “Museums do not hoard,” he said –– drawing an implied contrast with his description of the practice of source countries. And he asserted that the trickle of museums acquisitions is such a tiny fraction of trade that it “cannot be considered a factor in the continual looting of sites.”

While saying that museums should do “exhaustive due diligence,” he staked out a right to acquire an object in spite of a gap in provenance. Referring to a slide of a beautiful classical torso, he said: “Frankly, the refusal to acquire and bring into the public domain such a masterpiece [on dogmatic principle] is unacceptable.” If such an object were not bought by a museum, he warned, “it would be driven underground –– and I do not mean, by some miracle, to the place from which it came.”

Mr. de Montebello’s defense of the Enlightenment idea of the museum, as a place “where we can hope to grasp the totality of man’s mind,” was eloquent. (For those who missed it, he will repeat the lecture on December 7.) But with such important –– and, realistically, opposed –– values at stake as cosmopolitanism and cultural identity, archeological site information and the public’s appreciation of beautiful objects, more dialogue would be useful. Perhaps when he delivers his next lecture, Mr. de Montebello should invite Mr. Watson up to the Met for a debate.