I agree with you. I have a collection of American Modern Commemoratives, all graded MS70 or PR70 by PCGS. I am short of about 10 coins to have it completed. In all the years that it took to build this collection I had never heard of milk spots. Now I am simply stacking silver and that expression appears all the time. Could be that NGC or PCGS don't care about bullion , only to numismastic coins ?