Flight Crew are not the only kingpins of an Airline, anybody who works in an operational section is a kingpin.If the checkin staff don't check in any pax you would not have a reason to fly. If the Engineers don't fix the aircraft you would not have an aircraft to fly etc etc. Even down to the guy who drives the s**t wagon, if he didn't do his job you soon wouldn't have any pax who wanted to fly on your aircraft. Lots of people are kingpins to an airlines operation.