Maybe on paper, but not always in real life. A half dozen deadheading FA's, some in uniform, some not, all with Crew tags on their bags got boarding passes well before me. The GA went as far as printing a BP for me, when one of the FA's asked the GA if his girlfriend could get a BP, whereupon she got the seat that was on my erstwhile BP. (The GA gets points for aplomb, because when he was done with that transaction, and I said, "Hello, I'm Dr. Ahead - you called me up?" He realized that he could no longer give me a BP and quickly said, "I just wanted you to know that you are the very next person on the standby list."

I believe that a UA nonrev who is traveling "positive space" has priority over even a disserviced passenger on the standby list. One who is traveling "space available" doesn't, but often the line gets blurred between the two at the gate.