I knew a professor that pretty much just lectured and had his TAs administer coursework in the tutorial sessions. The only thing he had to do was put in the students' grades and double check the grades after his TAs graded them. He only graded twice a semester: midterm exams and final exams. Of course, he had tenure so he could do things like this and not get into too much trouble.
After I confirmed that I would go to the interview/recruitment weekend, one of my POIs emailed me the agenda from last year to give me a picture of what to expect. I'm still waiting on the finalized itinerary and agenda.
Invited students were asked for top choices of faculty to talk to so I'm expecting they're playing Faculty Member Jenga for the interview slots.
Future goals and aspirations inquiries are always a neutral ground for me (depending on my anxiety level).
As for the nightmare question, it would have to be anything too abstract. I've been asked, "If you were any cereal, which one would you be and why?" While great for twenty questions, I don't think it had merit in an interview.
Good luck!