Ann: Operations Update, page-382

You absolutely can't apply your experience of oil and water at the human scale to how it behaves as the micro/nano scale, the molecular forces start to dominate.

Even at the size of a relatively large insect the surface tension of the water (the amount water molecules like other adjacent water molecules) is enough to hold the water surface as a film and allow it to skate over the surface.

Plus it is all relative - flow occurs due to difference in pressure, but the amount of pressure drive for the gas/oil to escape the pores (if it has condensed out to oil as pressure drops) can be blocked by the water surface tension of the water drops that form over the pore and forces from the dislike of oil for mixing with water.

Polar and non-polar liquids don't like to mix and once again at molecular level the forces can be relatively very strong.