We refer to our passengers as customers, until we get to the load sheet where they appear as PAX.
On board the aircraft we have a very irreverant attitude to each others' jobs/titles with the Suspension/Brake Test Dept being up the front and the Galley Slaves down the back. I've seen meal trays arrive in the front labelled "front left pop/front right pop" on them (POP being poncy, overpaid pilot) but all done with good grace and mutual respect. But the passengers are always Sir or Madam unless instructed otherwise by the person concerned (VVIP corporate/charter provider so very few customers on board and often the same ones week in week out)
Before training as a pilot I served a short service comission as an infantry officer and the RAF always referred to us as SLF, that was the military and we didn't care so long as they didn't get lost or crash. The regiment I was very proud to serve in had two types of officers according to the other ranks: there were Wodneys, officers thwoo and thwoo, and Wuperts, officers who had come up thwoo the w**ks!