Morality is relative, and so is science.

There are many possible moral systems - it should be evident from the situation in the world today. If you can justify something based on your values/beliefs - it invokes your "feeling of justice". And there are many values/beliefs combinations. Not everything is pure facts of science (something like "single truth of what the world is") to compare against and tell what is the best, especially because of the uncertainty of the future.

Science is not "here on its own", but in people's minds. More importantly, it is spread in society. The rigorous methods/tools of science are one thing, but the gaining of knowledge as social debates (reasoning based) is another. The models that science builds are not "absolutely true". Therefore, the selection of models by social interactions (persuasion, truthfulness, financing, etc.) has similar characteristics as social morality.

To put it simply: the "fighting" of social models is the same as the "fighting" of scientific models.