I think the 'exception' that the guide book talks about was a foreign token, Robert. The sets that FM made up for collectors included ALL the gaming tokens that the company made that year. Some of the sets include Caribbean and South American tokens as a result. To my knowledge, every token design in the 'domestic gaming token' sets was actually used in a casino. There is some controversy about the 50c tokens as they were produced about the time that the regulation that allowed half-dollar tokens to be used, was recinded. There were probably some that were delivered to the casino but never put in play. Brass halves definitely were played at some clubs, though; I have some used ones.

Just to complete the story, there were a few dog track admission tokens in one of the sets. These are not true gaming tokens, but were gaming-associated as there was betting at the tracks.