I'm pretty sure it was a UA guy here who threatened JS denials. Also I'd bet the guy with his kid was a management type. They will trump you at mainline.
I had to DH to an outstation from ORD a few weeks ago, I never had the time to check in because of it being a last minute schedule reassignment. When I went to the gate podium to get my seat a Mainline pilot came over in a huff as I was getting my boarding pass and said something to me and the gate agent about UAX pilots shouldnt be bumping him and calling the chief blablabla. I just looked at him, stunned. The gate agent seemed happy to tell him I was deadheading. I just added that a airplane full of UA pax was waiting for me in XXX .. Maybe getting the facts before you go off the handle is a good idea, because it sure made that dude look like a jackhole to whomever witnessed it.