Both [cremation and burial] tend to make extravagant use of coffins made from valuable hardwoods such as oak and mahogany. In America the coffin may then go into a cumbersome and expensive burial vault. Unpleasant chemicals abound. A paper published in the Journal of Environmental Health in 2008, entitled "Drinking Grandma", warned about the public-health risks of formaldehyde leaking from cemeteries into groundwater. Cremations are dirty too. Dental fillings mean that they account for as much as a fifth of Britain's mercury emissions: regulations require crematoria to cut mercury emissions by half by 2012.
If economists complain about the money and resources wasted on coffins and other funeral nonsense, we are seen as cold-hearted and inhuman. But if you greenwash those objections you can get people to listen. I like the idea of alkaline hydrolysis, also called tissue digestion and resomation; hopefully mass production and legal and cultural acceptance will make it a cost-effective option in the near future.