The nice thing about the party is that everyone is in on the joke and they are in it together. They know from the beginning that there are going to be surprise

The nice thing about the party is that everyone is in on the joke and they are in it together. They know from the beginning that there are going to be surprises and much of the conversation is around this. The host can avoid an advantage by putting the bottles into blank bags then getting someone else to apply the numbers.