Answer:
If you have me, you want to share me. Once you share me, you won't have me. What am I?
I shoot but never kills
rub me and a genie might appear
My first is high my second damp my whole a tie a writer's cramp.
I can be entertaining until you realize some pieces have been lost.
As round as an apple. As deep as a cup. All the king's horses can't pull it up.