Pues a ver si se aclaran, porque les he preguntado sobre ello y me han contestado esto:
I"m sorry about the misunderstanding caused. Let me assure you that if you order "Buffy the Vampire Slayer - The Chosen Collection (Seasons 1-7)" you will get the additional disc.
Red packaging is an older version of the collection. The red and white packaging contains the same content with an additional disc including bonus content (40 discs total).
Mi no entender, oiga.