How to fund the maintenance and restoration of historic monuments and museums

Two recent pieces in The New York Times, “Tod’s to Help Colosseum Restoration” and ” ‘This Space for Rent’: In Europe, Arts Now Must Woo Commerce” have brought up the topic of commerical sponsorship of the maintenance and restoration of the cultural heritage. While there was no mention of advertising signage in connection with Tod’s pledged gift of $34 million for the multiyear restoration of the Colosseum, over the past year large advertising banners have appeared on the Musee d’Orsay and the Palais Garnier opera house and bring to mind the Bulgari ads that appeared on the facade of the Doge’s Palace in Venice. With cultural institutions in Europe (and in the U.S. too) in need of new sources of funding for their basic functions, might advertising ventures be preferable to sending out works of art for years at a time on moneymaking tours?