Agreed.PVC Conduit is not rated as waterproof (even though it is most times). It is a moot point as in most humid climates condensation will cause water to collect in it and it is very common to have the cables in the conduit submerged. This is why you still have to use burial rated cable in buried conduit.
Usually it draws in the moisture from above-ground locations and it collects, never leaves completely. I call it "differential thermal cycling" for lack of a better term or explanation.