Answer:
I look at you, you look at me, I raise my right, you raise your left.
I grow for a surface, even if you cut me. I continue to grow even after death.
I appear in the morning. But am always there. You can never see me. Though I am everywhere. By night I am gone, though I sometimes never was. Nothing can defeat me. But I am easily gone.
Stealthy as a shadow in the dead of night, cunning but affectionate if given a bite. Never owned but often loved. At my sport considered cruel, but that's because you never know me at all.
Hard to catch, easy to hold. Can't be seen, unless it's cold
Keep doing me to avoid lens dryness