I bet there is an exception for the playboy chips and they can not be cashed. The story I heard was that boxes of playboy chips were inadvertantly left in a corner at the place that was supposed to have destroyed the chips.

I say that there must be an expection to the AC rule that chips are always cashable because these chips were not considered outstanding and therefore not a liability. The chips were written off as destroyed. Hence there is no money set aside to pay for these chips.