One of the greatest sorrows of my life was the loss of my last and second baby through an ectopic pregnancy. I made the surgeon wait until the hormone levels were down and the baby was "dead" before I let them "remove" her. And it hurts just to type that. She was my baby and I loved her, if only for a few short weeks. I miss her in my life.
Among all the tragedies of the loss of that baby was that I was not allowed or given her "tissue," her body. It was disgarded with medical waste I suppose. It hurts to write that too. But, I know and believe that if God chooses to call her body at the resurrection on the last day, it won't matter if the pieces of her are scattered. With God all things are possible.
Recently I sat in a group of women discussing death and burial. Some wanted to be cremated and a couple wanted to have their ashes scattered someplace. Even though the Church doesn't allow that, they didn't think Jesus would mind. I kept quiet because I didn't know exactly what to say to all of that and nobody was asking me directly. But, I have thought a lot about it since then.
The thing is, although I believe God can and will reunite pieces of a scattered body like my daughter's, I don't believe He intended for us to treat the body that way. The danger of cremation is that the body becomes a "thing," just an object to do with as you please. It loses the sacredness that the body belongs to God and that body and soul will be reunited on the last day. And while, of course God can reunite all the pieces, I can't see anything that makes me see that God wants us to treat the body like a party balloon or some sort of toy. Bury the body to reverence it, to show respect.
Sometimes it seems to me that people in our headstrong generation are ready to throw out the "rules" without even asking the question of an authority who could give a reasonable answer. Instead, some of us write the rules ourselves based on wants and feelings. The Church and our tradition can point us toward good right order, what is best for us, what God intended.