I wonder if they all took separate flights, because of the danger to Apple of having them all on one flight. What if there was a tragic plane crash? Apple could end up like Lynyrd Skynyrd.
Most major corporations don't allow more than a certain number of employees on the same flight with a lower limit for execs. The limit at my current employer is 16 employees and 4 execs. Pretty common policy for exactly this reason.
When I was a kid, my parents would never take the same plane. They are very careful people... No wonder my dad directed an insurance company !