The montage of other clubs (at that time) show how much detail Kyoani puts around the NPCs, which ties into a narrative about the (wider) school. Many of the clubs linked could have their own series, really. (particularly the theatre club and the art club).
http://mangajet.com/2010/07/%E2%80%9...on-2ch-thread/
PS Liked the detail on Ricchan's drummin' passion.