Haha, yeah I knew those things, but I think I learned them from the Science Museum and from tv shows XD. Mythbusters taught me that even in today's world, your coffin can't stand the pressure of the dirt and would likely crack under the weight, and regardless, you'd probably suffocate within a couple hours as the oxygen very quickly depletes D: Not to mention embalming - thankfully we don't have to worry that our dead relatives are actually dying a scary death anymore!

I don't mind that the survivors band together in support for each other (I noticed it especially so when my friend killed himself, because you don't expect to have anyone your age die when you're young), but I think the place for worrying about yourself is at the reception, and the funeral is for mourning (and for some, at the burial site if they're being buried). Personally I need the actual funeral time to cry and mourn, especially at an open casket - I know there's nothing inside that shell, but I want to burn the image into my memory and get to think all the things I want to say to them.