I don't have a problem with it Biblically, OC got it right... "I don't happen to think it's a real big deal, cuz God can assemble me out of ashes anyway." I plan on being cremated. Plus, what about those Christians who were martyred by fire, or were killed in fires caused by accidents, etc.?
Unless one is preserved by mummification, etc., the body begins to decompose into organic materials anyway.
Gen 3:19 In the sweat of thy face shalt thou eat bread, till thou return unto the ground; for out of it wast thou taken: for dust thou art, and unto dust shalt thou return.