I'm sure a UAL guy will have the answer, but after commuting on them for over 4 years in my previous gig and listening to them talk, it's something like this.

At UAL, like a few other places, they have scabs. And like other places, the scabs are not well liked. Despite what one thinks of ALPA, all the pilots (non -scab) wear ALPA pins on their ties. Scabs do not. I'm not sure if they are entitled to representation or not. The "slick tie" as they call it is giving it away that they are a scab. Hence, if the guys has a "slick tie", he probably won't get much respect from anybody.