No matter where it's held, a funeral is a structured ceremony, with a beginning, middle and end. Each is intended to engage the living participants in activities which will transform their status within the community, provide mourners with a collective grieving experience, and celebrate a life lived. It's a socially-acceptable way for members of a community to re-affirm and express their social attachments.
Anthropologists label a funeral as a rite of passage, which affects everyone involved—including the deceased. His or her social status changes dramatically, from a living contributing member of the community to one whose contributions are in the past, and relegated to memory. But the status of each of the survivors—the immediate family most especially—has also changed. In fact, the funeral service can be the start of a defined period of mourning for bereaved family members, marking this transition in a uniquely identifiable way.
It could be said then, the focus of a funeral—no matter where, no matter when—lies in acknowledging change. And without doubt, human beings (as individuals and as a community) have trouble dealing with profound changes like the death of an integral member of the group. When you take this perspective, it becomes easier to understand the importance of ceremonially acknowledging the tear in the social fabric and the symbolic restoration of its integrity.