Here's my advice from all this as the former "go to" gate agent at my old shop for jumpseaters and non-revs alike. Most gate agents fit a personality, you need to know how to work with all of them if you don't want to get left behind.
It's true that a lot of gate agents out there just don't care, and they won't care. You can't get them to. These people usually don't travel, don't like people, and are very jaded since they get treated worse than other gate agents thanks to their attitudes. I actually worked with one guy who's favorite part was denying people boarding, he would get as gitty as a 5 year-old with an X-mas gift when we had an oversale or weight restriction. He also purposely sent down multiple jumpseaters to full flights and non-revs to non-existent seats just to yank them off the plane and give them false hope. He would even show up to flights he wasn't working and beg to be able to ruin the people's days, I used to let him until I saw the way he talked to passengers which made me sick to my stomach. I hated him, and I'm sure there's at least one of him at every hub. If you run into one of these people, you need to find another agent or a supervisor as they will sooner leave you behind then admit their fault. The same goes with gate agents who tell you they "don't have time" to get you on if you're listed and at the gate or show up before boarding, which is BS trust me, or agents who don't know the system but tell you they "don't know" in a dismissive tone rather than offering a solution. Even if they offer a solution, they may quickly run out of time if they appear to be slow, and you'll be left behind regardless.
If you run into any of those types of agents, I strongly advise that you go to another gate rather than getting a supervisor. Get to know the gate agents that will open up to you, especially any that want careers in aviation as they're likely to relate to you and want to take care of you. Look for those agents, if they appear to have down time and aren't working your flight, they're likely to help you if a difficult agent is being a jerk as far as listing, checking loads, or switching flights goes. Even if they're busy, they could point you to someone they know is cool and will help. If you don't know any of the agents, look for one that you see smiling and laughing with pax. The bad agents tend to look stressed out or have resting bitch face, though anyone can get stressed with that gig.
Last advice is never lose your cool. Even if you get the worst gate agent in the world, be the bigger person, and report it. Then it's all on them. It's important to know that even since I left customer service in 2011, most airlines have come up with waaaaay more through audits which makes it hard if not impossible for agents to hook up non-revs the way they used to. I would have been fired many times over using United's current reservations system. Keep that in mind when you're asking for favors even from the nicest agents.
