Fixing a leaky tap isn't going to help much during a flood. I don't know the numbers to be making any kind of judgement call and of course every little bit help. But sometimes a small issue really is so insignificant that fixing it has no noticeable impact in the bigger picture.

Often it can even be a great way for companies to look like their doing something to help and distract from the fact that they're the ones causing the bigger problem.