One theory advanced about complex art thefts is that the unsellable works are used as a chit among players in the massive global illegal economy stemming from the drug trade and other black-market activities. That concept arises here in the New York Times:

The theft “was carefully thought out, cleverly conceived and it was quickly executed, so that suggests professionals,” said Charles Hill, a retired Scotland Yard art detective turned private investigator who went undercover to retrieve a version of “The Scream,” by Edvard Munch, after it was stolen in 1994 in Oslo.

“The volume,” he added, “suggests that whoever stole it owes somebody a lot of money, and it’s got to be a major-league villain.”

“My best guess is that someone doesn’t have the cash to repay a loan,” he said.

Marc Masurovsky, a historian and an expert on plundered art in Washington, noted the possibility that the theft was “a contract job,” adding: “These works were picked out. Could it be they had been targeted well before the theft, and the exhibit was the opportunity to strike?” […]

“I think it’s a form of repayment in kind, a barter — ‘I don’t have cash, but I have these paintings,’ ” said Mr. Hill, the art investigator.