I think that IF Kishi included these fillers into the manga, we would all be pissed off, and tired of waiting for the real plot to start up again...
The anime is used by Kishi to fill the gaps, and also to help build up the manga better...
1. Naruto having Blue-Kyuubi eyes when fighting Kakuzo, we didn't know that until the anime.
2. Sora... we saw how Naruto could possibly transform into the fox, without using the deamon cloak... remember Soras arm would become like a monsters...
3. The Naruto vs Sasuke fight was EPIC in the anime... no manga could have done it justice.