DF:
how come the anti-death penalty mob is so concerned about it taking place in the USA under the conditions exposed here before, but just don't give a flying f* about places such as China
Probably because they think that the USA have greater moral principles, and that Americans care about the possibility that death penalty sometimes results in killing the wrong guy, which can obviously not be repaired. That makes death penalty more questionable than another penalty.
They do not expect a communist dictature like China to care about such a problem. That doesn't mean they support China. Just look at an organization like Amnesty International.
The truth is the anti-death penalty mob is selective about its principled opposition.
They focuse on the cases more convincing for their goal (= to put forward that death penalty is not "the best we can" in terms of justice).
That doesn't mean they approve death penalty for other murderers.