Mainline has something to gain--I currently do NOTHING--absolutely NOTHING to help out any non-pilot mainline employee...there is a lot you can do on a CRJ-200 to make or break those extra 3-4 nonrevs...if there are mainline/retirees sitting around the gate area, I will never do anything like upping taxi fuel, lowering cruise alt, or requesting ballast--ever...never...
On the other hand, when we had NWA pass benefits, with buddy passes (in our contract, btw), I frigging did whatever I had to to help out...
When we have a DAL mainline pilot, I do whatever I can to get that person on...but as for retirees/families of pilots/buddies of pilots, etc.--I care ZERO whether they get on my DCI plane or not--my family and buddies can't ride, so why would I care if their families and buddies get on my aircraft???