Your assumption seems to be that either it is a pure emotional value judgement (like donating to a dog shelter because you felt like it) or a perfectly objectiv

Your assumption seems to be that either it is a pure emotional value judgement (like donating to a dog shelter because you felt like it) or a perfectly objective judgement (ie. meta-reviews of randomised controlled trials). Perhaps that's a false dichotomy and there's a difference between supporting a cause based that is now supported by a significant body of philosophical and technical literature and just donating to whatever you feel like? There's nothing wrong with the later, just that you are kidding yourself if you think it is likely to be effective.