Rob Reich attempts an answer in the Boston Review. Tyler Cowen has a response here, including the following observation, which struck me as relevant to the deaccessioning debate (regarding the argument that the tax-exempt status of museums means "we" own the works they hold):
"In many localities some items are subject to sales tax and others
exempt, or perhaps subject to different rates. Let’s say that I spend my
money on untaxed items or lower-taxed items. Does this untaxed
expenditure—an indirect subsidy of sorts—imply that 'the public' should
have a greater say in how I spend my money?"