It's a while i'm thinking about it but imho i think is the time they give us the chance to flat out buy with coupons the fragments of normal rares like Yugito Nii, Kabuto Snake Cloak, Mu, Ginkaku and Kinkaku.

Maybe they could put some of them, at rotation, in konoha gift shop.

I literally find harder to bring to 3 stars yugito nii and Kabuto Snake Cloak than to recruit Itachi Susano'o or Hashirama Sage mode.