Why are we not crushed by gravity at the poles?
If our weight is the difference between gravity and the centrifugal force of the Earth's rotation, why are we not crushed at either pole area?
It's true that there are both gravitational forces and centrifugal forces acting on us. We're not crushed at the pole because the force of gravity is not strong enough to crush us. In fact, the very small change in gravity with change in latitude is tiny. However, you're right to point this out as it is different between the poles and the equator, however small its effect.