Freedom isn't an intangible, it's the core reason for the argument. Besides, a cost/benefit analysis, done properly, is not limited to monetary concerns alone. In trying to refute the original post, the argument proves it: There is a significant lack of understanding in presenting a proper cost/benefit analysis.
In the context of environmentalism a "cleaner planet" is mostly an intangible because on that scale it mostly doesn't affect anyone directly or fast.
Then it's the job of those who suggest we worry about it to properly portray effects that are worth worrying about. (BTW, I'm not a climate-change denier, just looking for concrete solutions.)
I called this argument as being "retarded" because it equates those in opposition to carbon credits as morally repugnant, on the same level as slave-traders. That's so extreme it doesn't even make sense.