Since we are looking at entropy with respect to class (whether we want to eat or not eat), entropy for blue & kit kats is 0 as we don't want to eat them at all.

Since we are looking at entropy with respect to class (whether we want to eat or not eat), entropy for blue & kit kats is 0 as we don't want to eat them at all. So there's no randomness. They are included in the IG formula but since they are multiplied by 0, they don't have any effect.