While I am unsure of what "trade tokens" are, if they are items that are exchanged for goods, then the difference would be that chips serve as a marker. They belong to the casino, and may only be cashed in for the actual value of the chip, and may only be obtained for the actual value of the chip. Strict interpretation granted.

I am unaware of any legal prohibition against my using a "trader token" to buy something else, and that person turn it in. There may be (the token may even state it), I don't know. But I do know that chips aren't supposed to be used for anything else, and if a third party tries to cash them in the casino can reject them (even confiscate them).

It does occur to me, what about chips that are discontinued? They may no longer be cashed in.