As for paying farmers for their past work and their ongoing work, there's nothing wrong with that. That's a very, very good thing. It should be done. However, doing it within the offset credits system is really disastrous. When you credit someone for doing something they've already done or would have done anyway, at the very same time you're giving a large emitter a licence to continue emitting in excess.
So there's nothing wrong with the idea that farmers should be recognized, but it shouldn't be done within the offset credits system.