Now before everybody gets in on the act - it cuts both ways. My husband is a professional musician and I am often asked by teachers (including arts teachers - dance, drama, etc.) if he could just put some music together in his studio for free for school productions, etc. He will do it when he has some time (being an extremely generous person) but he cannot put aside paying work when it comes along. This is often not understood and I could get all het up about it on his behalf but he just reminds me that people (teachers included) don't understand the way people like him (artists, musicians, etc.) earn their living. It is not their fault, they can only go by their own experiences, and most teachers I know would bend over backwards to help out. So, try letting them know a few times, maybe they will stop asking these questions. Bi the bi, I still get questions from my students about "Are you a real artist, or just a teacher?"