Only Blue Chests in S&P Scenarios. Bug, Lucky, Only Blues?

I have only gotten blue chests in the six E15 and E17 S&P Scenarios I have done. Is it supposed to be this way, am I super lucky, or is it a bug? Can anyone comment on this? Anyone getting white chests?

Because you are passing with flying colors =P. The number of survivors left alive impacts your rewards. All alive = blue chest

OHHH!!! I didn’t know that made it blue. Hell yeah! My weekend is filled with easy glyph leveling now. Rewards are better than OD.