Vegas
The fact he was going to Vegas explains a lot...and on Southwest too. Ever gone to Sky Harbor in Phoenix between 14:00 and 19:00 on a Friday afternoon. The Southwest and America West Terminals are one giant party spilling out into the concourses and the gates.
People are ready for a good time, thinking about winning and having some fun. I'm not excusing this jerks comment, but it is a fairly typical mindset for people going to Vegas. They lose all sense of reality upon arriving at the airport. The flights are the most boisterous, fun and noisiest flights going anywhere. Of course the return trips from Vegas are exactly the opposite :-(
Newarksmells