No, I have never needed one; my plumber friend suggested I might need one before realizing how low my pressure-tank levels were. I have a typical pressure tank, containing an air bladder, to feed my domestic water; less pressure than any municipal water.
Not sure why either. Do you not use a garden hose outside with a pistol-grip nozzle on it? Does it blow up every time you release the trigger and shut it off? Something seems amiss.
That's a good point. I typically switch off the water when I'm not using the hose