That was certainly bad service from a CFI. I assume you were at a good size FBO in Denver and I'd bet its 141 too. I won't defend the guy's actions, but I can see how it would happen. I work for a University 141 program and get the worst questions from certain students all day, everyday. There are some infamous students who tend to sit in the lounge and either brag about stupid things or else ask questions they should know how to answer. I've been guilty of being short with other people after a bad day. I do try to be more enthusiastic than normal when talking to potential students, but some days it is challenging. Like I said, I'm not defending his actions, just giving the guy the benefit of the doubt. That said, he could still be a jerk and mentioning the incident to the CP is a good idea if you meet him/her.