An optimistic cynics take
Sea water is amongst the more corrosive natural things you can end up dumping your metallic parts in. I guess a reapplication of whatever protective coating (probably Alodine or equivalent) might work although you probably need to chemically strip off the original damaged coating first, so i doubt its that easy or cheap to do.
But I would imagine catching the fairing before it hit the water would go some way to reducing the impact loading on the part. Impacts into water at high speed hurt quite a bit. Then again, if they think they can still use it even after one landing in water, then I imagine that they believe a net landing would increase the reusability. Sort of along the lines of if the Fairing can survive one landing in water and be reused, then it can survive 2 landing in the net and be reused twice for the same impact loads.
Just throwing ideas out there...