Should I cater to student interests? I am a tenured full professor in the humanities, teaching at an elite liberal arts institution. Currently our department is struggling to attract majors and student scholars in our particular humanities field, for a number of reasons - the academic work is perceived as exotic, irrelevant vis a vis the more valuable STEM fields, and considered intellectually "useless" for those whose primary goal is "getting jobs" after graduation. I would still like to teach courses in my area, because I consider this to be valuable. My institution permits me to teach whatever I wish, but our students have requested courses that are more general and more suited for non-majors and non-scholars. Does it make more sense to offer courses for those few students who desire deep study in narrow topics, or should I cater to student demands for general classes that appeal to non-humanities undergraduates? I do not wish for my courses to be seen as irrelevant, but I resist "trends" and the constantly shifting and sometimes fickle interests of the students in popular subject matter.
I'm not sure what your discipline is, but I understand the situation you're describing.  Does your school have a general education-type program in which you could offer some tantalizing courses?  We've had a lot of success with a course on "banned books," "Shakespeare on Film," or "The Vampire Tradition."  Such courses, if interesting enough, might bring more students into your major.  I taught a "Fundamentals of Lit" class that was intended for non-majors, and I had Engineering and Computer Science students who told me it was the first time they'd read a story in college and they really enjoyed the class.

The other point you raise somewhat indirectly -- the value of the study of humanities.  This is one of those "don't get me started" kinds of topics, because I believe the value of it is tremendous in a number of ways, but most important to other majors is the increased ability to communicate effectively.  Business majors may get what seems to be a "good-paying job" upon graduation, but without the communication and critical thinking skills they would learn in the Humanities, they're not going to progress very far.