Get new ones. I assumed that would be the end of it, and sure enough, on my next inspection they had brand new mess kits, all nice and non-reflective. I announced angrily. Oh, we did, sir. I suppose that's justification for having an officer around.
Someone has to understand the big picture.
Of course, when I made the troops get rid of yet another set of mess gear, they were probably wishing I would make myself clearer, like a sergeant would have.