THE TERM FILLER IS WRONG AND ANNOYING !
Such chapters or seasons are called anime exclusive or original anime episodes. Is that so hard ?
The only reason some people use that word is because it has a demeaning sound to it.
They want to point out again and again that specific episodes are not as good.
It is more like giving an opinion (bitching about the the absolutely obvious) rather than giving a description like
"anime exclusive" is.
Saying filler all the time is childish because: first of all, it is logically wrong since a story arc (even original) is a complete chapter of the story by definition with beginning, middle and ending and therefore it doesn't fill anything.
Secondly because a manga and an anime are different artistic mediums, the people who work for the manga are different from the people who work for the anime, there is a common backbone story but that's it. It is carved in some stubborn ungrateful heads but not in stone that the anime should follow 110% the flow of the manga.
Thirdly because it is like calling the other person stupid who apparently hasn't noticed that the episodes where Ichigo babysits the little princess are not as good as the episodes where he fights Grimmjaw.
And last but not least, all long running series have many boring episodes, it is part of the deal, get over it. You ain't saying something new bitching about it.
People who cry filler all the damn time, think they are the only ones in the universe blessed with the awesome knowledge that a chapter of the story in the anime doesn't appear in the manga (that they don't buy). And whether it's TV series or music albums or whatever people who say filler are the people who don't really care about it that much. -Dude, Leteralus from Tool had one good song but the rest was filler... -No, slow songs, boring ambient sounds meant to built anticipation, long intros; all part of the game
Don't mindlessly repeat stuff.

