Casual-Fans are fans who aren't particularly into their fandom. They enjoy it, know some trivia, see some movies, have some stuff. Casual-Fans are more laid back.
Note: It is possible to be a Casual-Fan in one area, and a Proper-Fan in another. Or a Casual-Fan and a Psuedo-Fan, etc, etc.

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A person who enjoys the act of tailgating more than the sport itself. In many cases, the casual fan knows nothing about the actual sport being observed. This often results in the misuse of sport terminology, mispronounciation of athlete names, and overall confusion with rally cries.