While the professional courtesy of offering the jumpseat to another pilot is at the Capt's discretion. It is a huge bummer when you see a guy (or gal) using the jumpseat to further a political agenda [SCABS aside] or personal grudge. The jumpseat is a benefit that we all have the opportunity to screw up, I'm sure that each company would jump at the chance to save monthly CASS fees if given the proper reason (like an pilot/union food fight). Just my two cents.