past-poster n. a gambler who places a (surreptitious or illegal) bet on a game or race after its outcome has been determined. (source: Double-Tongued Dictionary)
Further reading
Chase from Jacksonville, Florida, grew up in Sacramento, California, where kids played Rochambeau instead of rock, paper, scissors. Why the difference in names? Nobody knows. Folklorists call this a choosing game, and while the hand-game itself...
In 1916, a small-town newspaper in Pennsylvania printed a fanciful item about a local gathering with a guest list that included, among others, Miss Ella Vader, Mr. Ray Zor, and other punny names. This is part of a complete episode. Transcript of...