It comes up in the chatbox when you start a game.
What does it mean when 2 different game numbers come up. For example (and I'm just making these up completely), I have played a game where it says, "82134 from Tokyo" and also "82755 from Tokyo." Why would there be two different IDs for one card combination???
Obviously, if the code was merely a 5 digit code, it would cover only 100,000 [minus one] possible game combinations. And, with the number of Dom. cards, there are--essentially--an infinite number of possible games. Why the city codes added to the end? Is this some sort of secret CIA code, so that we are making the world safe from terrorist attacks while also having fun playing the game?
On one hand; I'd like to do my part in making America safe.
On the other hand; I'd hate to do anything that benefited President Trump in any way, shape, or form.
So, what is the "secret history" [hat tip: Donald X] behind using city names in the identification of individual games. Inquiring minds wanna know.