Do Possums Really Exist?

On my way home from work today, I saw a dead possum on the side of the road. I've seen many dead possums in my lifetime. However, I do not think I've ever seen a single live possum. Not even in a zoo. This makes me question whether they even exist at all. I bet there's just a factory somewhere that manufactures all these realistic looking “dead possums” and people drop them at random points along the road.