Leave the taps open until nothing spits any more.
As stated above, if your lines have dips in them, water can remain there. If there is enough space, any residual water will have room to expand and not hurt anything. The real problem is around seals and valves. Even micro drops of water can cause seals and plastics to expand and break. Any water droplets left in your water pump could freeze and cause problems with leaking once everything thaws out.
By "pumping the pink" you are truly replacing any water droplets or low spots with RV antifreeze (which still freezes to a slush, but does not expand when it freezes).