I am not about to make a definition of "fantasy" chip now, but a good definition of "fantasy" chip would entail:
(1) it is NOT a reproduction,not counterfiet, that is, we are not talking about chips that look like genuine/known chips. Fantasy chips have new designs that have been dreamed up by the manufacturer. Fantasy chip may have an old look to them and may be done in an old style, but the design/layout has never been seen on an old chip. (A dealer who tries to pass off Fantasy chips as genuine old chips has one clear advantage -- no one can find an old chip to compare to it as one could do with reproductions.)

(2) any old collectible could have Fantasy counterparts, but for our purposes, I think we should limit ourselves to Fantasy chips that could be confused with genuine casino chips. for example, they have the word "club" or "casino" on them along with a name. Having a place name like "Las Vegas" would help having it included in the definition. I don't think the following flag chips, for example, should be consided fakes or fantasies (they are just harmless home poker chips):

Robert