(Mav complains that funerals are useless. The following is my response.)
I think you're right. But I think I understand why people use the ritual.
Human psychology seems to be such that if a human can't look around and see other people observing the exact same thing, then maybe it didn't really happen. Without something like a marriage, then it might be considered an ongoing coincidence that two people are living together. Without a coming-of-age ritual, a child doesn't psychologically break with the past in both his own eyes and those of the people who know him. And without a funeral, to a certain way of looking at it the deceased might have just gone on vacation, and then by the time you notice he hasn't come back, the memory has just degraded, and fades off, until it's just a vague and poignant smudge of something lost. I think being with others at a meeting specifically intended to commemorate a death also helps reinforce connections to replace the one that's gone. And as a well-known principle, concentrated events of emotional intensity are remembered far better than a drawn out solitary process. And remembering is key.
I'm thinking of my paternal grandmother as I write this. I haven't sat and really thought about her since she died about two years ago. She was past ninety and she lived with my family, so was clear of mind and not alone right up until her heart finally gave out. I will always miss her and remember the things she did for me and my parents and siblings. And the things she liked to do and that made her happy in her quiet, patient life. "Minneu, minneu" she called my cat in French. She wrote letters. She played piano at the old folks' home, even long after her husband had died from Alzheimer's and no longer lived there.
These were things that I knew about her and cherished. But I didn't know how others felt about her. My mom got up and delivered the most beautiful eulogy I have ever heard. She said, "Bertha was love. Everything she did was motivated by how much she cared for others. She inspired me. And she will always be with me." I would never have missed hearing that for the world.
I'm crying now as I write this. I think I cried at the funeral, but it was distant. It was too stark, too foreign, too dreary, despite the fancy, cream-colored parlor and the sympathetic doormen in sunglasses and black suits. It didn't mean anything then. It wasn't about her, it was about fulfilling an expectation. I wasn't glad I went then, I just let the tide carry me. But I'm glad now because I was there for the other people who were there who were also grieving. It was those people who needed it. And I found out how much grandma meant to the people close to me. I knew that she did, but it's not like I discussed it with them while she was alive: "How do you feel about Grandma? Is she a nice person, or what?" Well, duh. But when she's gone, it's not obvious anymore.
Yes - it's a macabre and maybe even ugly thing to sit around a dead body and peer at each other and say "this was a good person, wasn't it?" But you do it for yourself. Because it also helps you realize that those other people you are there with, care about each other. They would do this uncomfortable ritual for you, too. And they would remember you. As you would them.
They would complete each others' picture of you. And they would say nice things. And they would pool their pain to help burn it into indelible memory. Like a wax seal on an envelope full of beautiful writings.