I think the warranty mentions cosmetic items being covered for 1 yr. / 12K mi. Most dealers will try to use this as a basis for excluding the wheels.
The first option is to try a different dealer.
Different dealers seem to handle this situation differently. The fact is, the wheels are defective. The copper base plating has separated from the aluminum, why? Poor prep. and/or defective/ incompatible materials? This is not normal "cosmetic" wear for a chrome wheel and indicates an underlying problem.
You might also try directly approaching the service manager from the angle that you believe that the delamination of the chrome is related to a "structural or manufacturing defect" and that the exposed aluminum will be subjected to continued and accellerated corrosion and structural degradation, all of which calls the "safety" of the wheel(s) into question. If he says the wheels are fine, just have him put in writing, on a dated company document .
Then try a different dealer.
Maybe one of our "jailhouse lawyers" can get the actual total number of U.S. 2000 and 2001 wheels that have been warrantied via a "freedom of info" filing?