I have heard of situations where a student will boast about having a "4.0" in terms of their science courses, but the full story/overall GPA was less than impressive. Needless to say, that person was confused when they received no interview.
PharmCAS calculates science, non-science, math, and overall GPAs. But not all pharmacy schools use PharmCAS.
I have heard the same about pharmacy schools and how they favor a candidate with a Bachelor's in one of the Sciences versus someone with just the pre-reqs. Plus there are the other (what I feel are requirements) to being a complete candidate (extracurricular, pharmacy and life experiences).