Christians believe that when you die, your soul leaves your body, and enters heaven (or hell).
Athiests believe that you never had a soul in the first place, so you're merely tomorrow's fertilizer.
All other major religions also believe that your soul leaves your body upon death, leaving an empty shell.


With all that in mind, what does it matter what happens to the body? I personally believe that dead bodies should be turned into fertilizer, as long as the family of the deceased is agreeable. It saves space that is wasted by graveyards, and is what nature intended anyway. Cremation is good too, because the end result is the same. I believe that going to efforts to protect dead bodies is a waste. Just let nature take over.