I actually have given some thought to that as well. In an industry designed around putting people in different places but needing to service the process, it’s challenging to have the right staff in the right place at the right time.
Sadly, the desire to maximize profits means filling all the seats just a little more than 1x. This is on top of the needs they have to move their own employees around for work — forget the personal trips.
Interestingly, I am sure a part of this process is also based in the regulations that govern who can work on a plane, when, etc.
Certainly a complex mess with no simple solution.