as an applicant, would it make me more desirable to schools like UCLA/Cal/Stanford?
Does having A's in Math (Calculus) make you stand out when applying as Philosophy/Psychology majors?
Sure, although calculus is not particularly important in philosophy, but A’s in high level classes that differ from your major sort of show you’re more well-rounded. A’s in Calculus won’t necessarily give you an advantage over someone has a higher GPA than you, though…
http://psychology.berkeley.edu/students/undergraduate-program/lower-division-requirements-fall-2014-freshmenfall-2015-transfers indicates that Berkeley psychology requires three lower division quantitative courses; calculus can fulfill one of these courses. All of the schools have some quantitative methods requirement, for which statistics is typically recommended.
For philosophy, strength in math often goes hand in hand with the use of logic in philosophy.