Answer:
You saw me where I never was and where I could not be. And yet within that very place, my face you often see.
In we go, out we go. All around and in a row. Always, always steady flow. When we'll stop, you'll never known. In we go, out we go.
Although I'm not an insect, some people found me very difficult to exterminate. They called me something like 'insane priest.' The first half of my name means the same as 'scrape,' & my last three letters are a metal. Who am I?
Always wax, yet always wane: I melt, succumbed to the flame. Lighting darkness, with fate unblest, I soon devolve to shapeless mess.
Some live in me, some live on. And some shave me to stride upon. I rarely leave my native land. Until my death I always stand. High and low I may be found. Both above and below ground.
People take me on walks and I run and have fun. What am I?