By the way, Richard Sandor is quite ethical. His markets although they are very risky, provide a good investment choice for the speculative.
Yes, at the very least it is market based and I initially thought it was a good idea. However, I have come to realize that selling carbon offsets is like a doctor who treats a cancer patient with nothing more than painkillers. The patient feels better but the problem remains. Actually, more accurately, it's like a doctor prescribing placebos for the cancer patient but tells him or her its a painkiller. It might help them feel better but it probably won't and the patient will still die of their untreated cancer. The doctor has presented the placebo as a solution to the cancer but it doesn't even address the illness. That, in my book, market based or not, is fraud.
The other example that comes to mind (and I can have quite the trivial mind) is Wile E. Coyote's little umbrella. In the cartoons, he whips out this tiny umbrella for protection just before he's about to be crushed by a huge rock. He thinks it's supposed to help, but it doesn't. It can't. With carbon offsets, you may as well be the Acme Company selling tiny umbrellas to boulder imperiled coyotes.