[abathur]

Is there not a chance that the professor might, in fact, be correct in her assessment of the motivation of these upperclassmen and decent?

It's not like anyone's proposed sentencing them to death. (Or any punishment at all?)

Most universities have gobs of overlapping official and unofficial tutoring programs both broad and subject-specific. Enterprising scholars will also inevitably find a way to announce independent tutoriing services.

Students who are enthusiastic about sharing knowledge, making a few bucks, or adding a line to their resume generally don't have trouble finding such opportunities to share their knowledge and help others succeed without having to audit a course.