Since, according to maximizing utilitarianism, any act that fails to maximize is wrong, there appears to be no place for actions that are morally admirable but not required, and agents will often be required to perform acts of great self-sacrifice. This gives rise to the common charge that maximizing utilitarianism is too demanding. […] How should a utilitarian respond to this line of criticism? One perfectly respectable response is simply to deny the claims at the heart of it. We might insist that morality really is very demanding, in precisely the way utilitarianism says it is. But doesn’t this fly in the face of common sense? Well, perhaps it does, but so what? Until relatively recently, moral “common sense” viewed women as having an inferior moral status to men, and some racs as having an inferior status to others. These judgments were not restricted to the philosophically unsophisticated. Such illustrious philosophers as Aristotle and Hume accepted positions of this nature. Many utilitarians (myself included) believe that the interests of sentient non-human animals should be given equal consideration in moral decisions with the interests of humans. This claims certainly conflicts with the “common sense” of many (probably most) humans, and many (perhaps most) philosophers. It should not, on that account alone, be rejected.
Alastair Norcross, ‘The Scalar Approach to Utilitarianism’, in Henry R. West (ed.), The Blackwell Guide to Mill’s Utilitarianism, Malden, Massachusetts, 2006, p. 218