Literature tends to deal with human experience in a radical and subversive way. The student of literature is invited to lay aside prejudices and preconceptions in understanding the meaning conveyed.
Unfortunately schools, as the bastion of conventional values and perspectives, are ill-suited to encouraging the student in this task. Instead schools tend to undermine understanding and discourage critical thinking through a conservative, majority-rules approach to interpreting a text - the ignorant leading the blind. Nevertheless a few students do manage to see anyway.
Is literature education worth it for the few?
I agree that the institution of schools are inherently conservative. As institutions, could they be otherwise? Indeed, is not the very notion that we should look toward an institution to promote a challenge to conventions somewhat absurd? Of course, part of what should be taught in school is the ability to think critically which will allow the individual; to develop his or her own understandings... even to question conventional wisdom or entrenched thinking. The problem, I believe, does not lie so much with teachers, but rather with the administration. Administrators in general seem to be a rather conservative lot and have little concept of the worth of art or culture beyond its value in financial terms... or as a means of promoting that which is truly important: literacy skills, math skills... the things which show up on standardized proficiency tests. It never dawns on them that music may have worth beyond its link with mathematics, or that visual art may have a value beyond a means of further illuminating history or geometry or other practical fields of study.
For quite some time, the arts have been employed as a means of conveying certain conventional moral or ethical ideas. I remember the continual push to recognize the moral or the message that the writer or artist sought to convey... and I agree with you that there is often this notion that only the interpretation agreed upon by the teacher and the majority holds any value. The possibility that Shakespeare challenges traditional notions of the clear separation of "good" and "evil" and the eventual triumph of "good" is not something likely to be popular with educational leaders. It wasn't even popular with Tolstoy. Can we really expect that the institution of education will embrace the questionable ideas put forth by Blake, Shelley, Emerson, etc...? Are we really surprised that not only the Beats or radical thinkers such as Sartre and Nietzsche represent a threat to traditional/conventional values... but that Baudelaire, Rimbaud, Goethe, Shakespeare, even Dante do as well? Can we really be surprised at the efforts of school leaders to clean up the arts when we consider that a vast portion of the whole of art deals with such issues as sex and violence? Its no surprise that so many young readers flock to certain writers such as Rimbaud and the Beats and Dostoevsky when so many of the great writers of the past have been sanitized and painted in the most boring manner. One of the greatest joys, I think, is rediscovering great literature for oneself... but unfortunately the lock-step mode of teaching it can turn a great many potential readers from ever wishing to explore it on their own.

