Engineers have shown that random seating is more efficient (from the point of view of the amount of time it takes for everyone to get into seats) than assigned seating.
Engineers? I'll see your engineers and raise you physicists who have formally proven that ordered seating and entering an airplane is faster than entering randomly.
When the stars threw down their spears
And watered heaven with their tears:
Did he smile his work to see?
Did he who made the lamb make thee?