This doesn’t fit with anything really except that I’m teaching a college course this semester, but I found this discussion on Ask Metafilter quite interesting: If I want to drop into college courses, should I ask the professor for permission or should I just sit in?.
I’m sure my view has been expressed as a blend of the various responses. If the course cap has been reached, sorry, auditors need to get in line. If it hasn’t, and the presence of people auditing the course has no negative consequences for the registered students, I’d be happy to let them stay. I wouldn’t grade their assignments and exams, though, and I would prefer registered students during office hours and in-class discussion. I wouldn’t stay late to answer an auditor’s question; I would, for a registered student.
If someone were to “sneak into” my course, I’d be feeling a mixture of things: I’d be flattered that someone wants to hear what I have to say, just like with every student. I’d be irritated by the person not asking for my permission or following official protocol. And finally, and this would probably be the overwhelming feeling, I’d be confused why it didn’t occur to the person to ask.
In the end, I’d probably kick a person who “sneaked in” out of the class. Even if I give something away freely and with joy, taking it behind my back is stealing.