Unless you are severely ashamed of your company or what you do for a living, why jumpseat out of uniform going to or from work? I always wear my uniform and never, ever had a problem getting on. If I see a grumpy gate agent, I do what I have to and then position myself so that the pilots will see me from the cockpit, works everytime and I always look myself to see if there is a JS waiting by the gate. And while I am at it; cudos to the gate agent at MCO for J6, DL, and AA. They are awesome, friendly, some even good looking, and they always get the old Viking to work on time.