Does it make sense to do cosmetic treatments when the foundation is crumbling?

The Naumburg Bandshell in Central Park, built in 1923 and the site of free outdoor concerts is in desperate condition. According to an article by Kia Gregory in the June 25, 2014 issue of The New York Times (“Gold Touches Up Sullied Band Shell in Central park”), cosmetic cleaning and regilding were recently completed in time for the summer 2014 concert series. While the cosmetic treatment cost $15,000 and a full structural conservation treatment would cost $5 million, does it make sense to spend money to make the surface look nice when the structure beneath is crumbling?