Unless the outcomes to all students involved are zero-sum, it's not hard to have a model in which a single student getting an artificially higher grade through

Unless the outcomes to all students involved are zero-sum, it's not hard to have a model in which a single student getting an artificially higher grade through some unfair mechanism is a net utility gain. It was one of the arguments specifically presented in my intro-to-ethics class (though it was not cheating, it was a student asking their professor (who was a utilitarian) to give them a slightly higher grade; for pure utilitarianism the mechanism that results in inflating the grade is irrelevant).