Bentham and Utilitarianism

Jeremy Bentham said we are governed by two sovereign masters. Legislation should all be about maximizing the balance of pleasure over pain, he says. But why is that relevant to questions of justice? Here's an example where it arises. If huge majorities dislike seeing women wearing burkas on the street does that justify banning wearing of the burka? Yes those who would like to wear it suffer some unhappiness according to the utilitarian calculus but it's outweighed by the greater happiness of the majority. I think that's an example of what goes wrong with the utilitarian calculus for its failure to evaluate or to assess or to judge the quality and the moral significance of the preferences.