So ironic I read this thread. Coming home from a meeting this week and in line at First/Med to drop a bag behind a very agitated man wearing casual business attire. After a few more minutes of the line not moving, he grabs his bags and races through the lobby to the lobby agent and demands she goes through the F/M line as "there is no way some of them are in the right line - you can tell by the way they are dressed!" I watch the interaction and he proceeds to get mad at the lobby agent telling her the line is supposed to be F/M only and she's not doing her job. The agent tells him she cannot discriminate against someone based on what they are wearing and says " you'd be surprised Sir". As medallions we enjoy the exclusivity of our own lines etc but then get snippy when asked by agents if belong there, I see it all the time.