Here's what I don't get about jumpseating. And yeah, I'm not a regional/ major airline pilot, so maybe I should just stick to the CFI forum, but in this case maybe an ignorant outsider viewpoint might make a little sense.
The way I understand jumpseat agreements, is they are supposed to benefit all parties involved. If I own airline "A," I want my pilots to be able to jumpseat on airlines "B" and "C" so they can get to and from work. In return, I extend the same benefit for "B" and "C" pilots to jumpseat on my airline. Tit for tat.
If the Captain is responsible for the safe operation of a flight, how does a particular jumpseater affect said safety? How does the jumpseater, no matter what airline they fly for, affect anything pertaining to the safe operation of a flight?
Stepping way outside the box, if I were an airline CEO, I would not want my captains making jumpseat decisions based on a political agenda. It's bad for business. Enough of airline "A" denying seats to those upstart "C" guys and eventually airline "C" will say "screw you, no more seats for you!" Now I can't get my guys to work.
Assuming the safe conduct of a flight is not an issue, why in the world are Captains allowed to make these very arbitrary jumpseat decisions? A good example would be Velo's example of a Captain denying a seat to a company pilot simply because the Captain himself didn't ask for jumpseats. How does that make any sense, and how does that help the company? Saying it's the Captain's prerogative isn't much of a reason, IMO.