Why should people be more inclined to think that the foreseeable negative side effects of a policy are intended, whereas the foreseeable positive side effects aren't? Supposing there are both negative and positive side effects of the very same policy - side effects because incidental to the policy's main objective - can those who initiate the policy sensibly be blamed for the former while being given no credit for the latter?
I think the first question is quite separate from the second. The first is about the asymmetric attribution of intention (which I agree is hard to justify), whereas the second is about the asymmetric attribution of blame/credit.
If (in the example discussed) a company adopts a programme in order to boost profits, which also has the effect (irrelevant from the company’s point of view) of benefiting the environment, then we may certainly be glad of this side-effect. But those responsible care nothing for the environment, so praise would seem utterly misplaced.
On the other hand, if the company adopts a programme in order to boost profits, which also has the effect (irrelevant from the company’s point of view) of harming the environment, then we may regret this side-effect. But blaming the company is, I think, more intelligible here than giving credit would be in the previous case.
Here’s the reasoning: in the former case (intended profit plus incidental greenery), all the consequences are good, so there’s no doubt that this is worth doing on any perspective. It’s not a contentious action at all. But the profit motive constitutes the full explanation, so no green credit is due.
In the latter case (intended profit plus incidental pollution), the consequences are mixed, so a cost-benefit analysis clouds the overall quality of the action – at least, from the point of view of those asked to pass judgement. The company notes the expected resulting pollution but doesn’t rate it as a cost. This is where the blame can get some purchase: it’s in the fact that the company chooses to rate environmental effects as irrelevant.
This factor also exists in the former case, and so blame for it there should be as legitimate as in the latter, but (a) in the former it doesn’t result in any actual harm, and (b) the respondents weren’t asked to evaluate the fact that the company in general doesn’t care about the environment.
Blame given in the latter case reflects not so much a perceived link between specific intentions and consequences (present in the latter but absent in the former) as it does the company’s more general eco-apathetic attitude. The desire to dish out this blame will flare up more strongly when the attitude causes harm.