Dont use logic else risk offending the blowhards. This is an antiquated system, as if in this day and age we are going to open the door in the middle of an emergency and hail all the pilots up to the front. We may ask the FA to go through and get one, look at the credentials and see they are a JS then bring them up, but really, the flight crew doesn't need to always know who is in back.

I have, without a friggen doubt, had more MAINLINE pilots fail to act properly than any regional pilot. Some show up in street cloths, dont bother checking in at all if they got a seat etc. The LCC guys/gals are awesome, always very respectful and properly dressed. I think it goes unreported about mainline because people fear any sort of retribution, as silly as that may be. So before they get up on their high horse it would be best to look inside first.

At the end of the day, you either are a captain that just wants a quick hello and understands that people are just trying to get to work or back to their home/family with as little issue as possible, or you are the type that feels they are owed some huge debt of gratitude for letting you on "their" aircraft. I do however agree about the dress code policy if sitting up front, we dont want passengers to see pilots going up with jeans on, might make them feel we are not taking this seriously enough.

Either way, I find it easier to just say "excuse me gentlemen/ladies, just wanted to see if I can catch a ride". At that point I take the cues from them.