Environmental Intensity isn't affecting all models

I found that the common denominator is the bounds scale: those with bounds scale>1 are affected by the environmental intensity while those<1 aren’t.
I don’t think this is normal behaviour so I hope someone could enlighten me

I’m building a space scene and I’ve noticed that increasing the environmental intensity, only two models are influenced by it, the others are unaffected.
I checked every settings but they are the same for all the models.
I’m afraid i don’t have the slightest idea on what’s wrong.
In the attached images you can see the same shot with environmental intensity 1 and than with environmental intensity 300.

Thanks for your time,

Matteo Dell’Acqua