Giving the instructor his due?

At the end of a tape critique session, the other broadcasting school students and I got up to leave.  The instructor, a St. Louis radio veteran, asked sarcastically, "What? No 'Thank you for nurturing our careers...'?"  No one batted an eye at this, as we all understood.  Radio is a precarious business.  When you have to move from station to station, earning only modest amounts of money, how could you not be at least a tad jaded and acerbic?