"it would have the effect of reinforcing the belief of those who are having chips fixed that they can get away with it. Just a thought."

You hit the nail on the head. IMO, The only thing you can do is ask for a written statement every time you buy an un-drilled chip also known in drilled condition. If the seller will not do it, you can bet he is selling a chip that was drilled at one time.

They are also repairing broken chips.