Bryan, welcome to the hobby and the BB.
Bill Boreland had them made in the early 90's. Bill is dead.
John B is right, Bill made them to make money.
Gamblers General store bought all that remained from Borelands estate about two years ago. They sold them for $1 each. Boxes & boxes of them. All the ebayers stocked up. GGS sold out.

BTW, Boreland made a lot of counterfits also. Be aware, if you are looking at Nevada or Die Card mold, hot stamped chips to buy.