Answer:
I am a protector. I sit on a bridge. One person can see right through me, while others wonder what I hide. What am I?
The more you take away from me the bigger I shall get.
I am free the first time and second time but the third time is going to cost you money.
I can go through glass without breaking it.
What room do ghosts avoid?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.