Answer:
I am commonly ate before I'm born and after I'm dead.
I am a shimmering field that reaches far. Yet I have no tracks and am crossed without paths.
I tremble at each breath of air, and yet can heaviest burdens bear. What am I?
I am a sound made by felines when petted.
I am free the first time and the second time, but the third time is going to cost you money. What am I?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.