Don:
If I had been bidding on that E-Bay item with the Celine Dion AC chip, I definitely would have "assumed" that it was only ONE chip. Although that chip was long ago sold out at Caesars AC, it is still "active", meaning it can still be cashed in, or gambled with, at Caesars. No seller in his right mind would sell two $25. chips ($50. total) for a $ 31.99 minimum bid. Just chalk it up as some poor choice of wording on part of the seller.
Don