Attending Other Dancers' Workshops

I heard a story on the weekend about teachers who send their students to workshops but don't attend them themselves. Apparently, they don't want their students to think they aren't capable or (heaven forbid) that they don't know everything. My response was, "What?"
The truth is that an individual doesn't know everything there is to know about belly dance and never will. As a teacher, professional performer or international star, we still have to train and we still have to learn.
I told one of my students that if belly dance was a open field, I would know a blade of grass. What happens if a student asks me something that I don't know the answer to? I admit I don't know the answer, look it up or ask someone I think might know. We are humans, not gods. We are equals with our students. I will go to a workshop with my students to learn. If they do better than me at the workshop or remember more, good for them!

This topic brought a question to my mind. Do dancers invited to give workshops at national or international events ever take their fellow guests' workshops? I've personally not seen it, but I haven't been to too many big events. I know that after giving a workshop you are tired and you probably need to prepare for dancing at the gala event, but would you if you had the time? Personally I would.
I don't know if it is frowned upon by the community or if it's just not "the done thing". If I were ever to be invited to give a workshop at a big event (one can dream) and did someone else's workshop, how would that be received?

Please send me your thoughts about this. It'll be interesting to see what others think.