Casket Lift

Why is it that when I go to a funeral, they show that the upper body? why not the whole length?

Well, the point of going to a funeral is to pay your last respects to the deceased, and it seems logical that you want to do this by looking at the person's face, as one looks at the faces of people living in communicating with them (we do not look at their feet). It's just a social convention, really. In addition, funeral directors may not fully clothed (as, put shoes on) the bottom half of the body.

Well, in some cases, the person may not seem so great after death. They could have died from lightning or fire or other. The funeral is already very expensive because it is the people with the sick family member may not have the money in the budget to pay to make up the whole body. In other cases where the person died of old age or some physical internal conflicts, it is also frightening to see someone dead in its entirety.