I can only answer with a guess myself. First off I am assuming these come from China as most of the counterfeit US coins do. This could have just been a test at some point to see if they could make a token to later redeem to the casino, but in large numbers not just one at a time. Problem was that they used a bi metal and just plated it and casino folks know they have the brass ring. It would cost to much if they actually used silver and brass. I think (and could be wrong) the first one was found at the Four Queens.

Dennis