Before expansion perhaps thirty years ago all games played Lamade single elimination. There was an issue with China that resulted in then being banned for a long time. After a time more teams added and Volunteer built and tournament going to double elimination as it is today. This year change was more teams.. Foreign Teams that lost often get to play a game in Lamade before going home. Championship games for International and US played on Lamade., Saturdays with World Championship Sunday.
Lamade stadium holds more people which typically attend the US games. Usually there is plenty of room for fans of the foreign games. All games move to Lamade on Wednesday
Most of the prime time games are played at Lamade. Being that all the local American games are played on this field was due to tradition. And as you stated except for the Championship game.
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