Morality is a comparison between one's normative standard and a given circumstance. An entity can apply moral standards to others within its society, itself, another culture, another species, a fictional character, or an inanimate object. All it's doing is developing an impression of intent (accurate or not, applicable or not, real or imagined), and evaluating it against a given criteria. Where these criteria come from is the point of controversy Abrahamic religions claim to answer, and by implication they brandish the threat of moral relativism as though it were applied within a society, rather than across cultures -- the appeal to consequences that frightens many people from this discussion.

A society is an end in itself, and it is only with the adoption of a standard of evaluation that it can be judged. If science, for instance, becomes a concern of many people, then those people will likely be motivated to evaluate things with scientific criteria. A society could as easily define any arbitrary criteria, and attempt to sort through reality with that -- such as what happens when simple causality is applied in conjunction with anthropomorphism, producing gods, spirits, etc. But once we choose, or have chosen by a natural selection of ideas over a long span of time, the criteria by which a society judges itself, and others, is not something easily altered.

When one addresses the subjectivity of moral application, one must turn their attention to the subject itself. Where does the subject's views come from? The subject is largely a product of its society -- so what is, is simply a product, an evolution, of what came before it. There is simply an unlikelihood of broad variation within a generation's morality in a given society (barring unusual strife). And this is circular, because the society, too, will be the product of each of those subjects; so whatever it is the individuals do in a given society will be at least somewhat acceptable to themselves, and by definition, that society.