I wonder could you exploit this if you're the company who has the book. Buy it as a normal user from the other company for $23 million. They buy your copy for

I wonder could you exploit this if you're the company who has the book. Buy it as a normal user from the other company for $23 million. They buy your copy for $22 million. Wait until the end of the returns window (assuming Amazon enforce one) and return it for $23 million. They try to return it to you, but it's too late. Probably the bookshop notices something is wrong on the $23 million item, but maybe you could make a few thousand this way.