Funny, I never hear of large commercial airliners making 9-minute flights for logistical reasons? What logistical reason would that be beyond 'Elon doesn't want to travel all the way to that airport when there's a closer one?'
Aircraft are moved all the time for logistical reasons. These are known as "empty leg flights".
For example if you will fly from Chicago to NY, but your charter plane will arrive and disembark in Milwaukee. After disembarking, it will take a short flight empty between the two airports.
And all of this is transparent to the passengers. It's not like the charter company says, "Hey if you meet the plane in Milwaukee you can save us the fuel". Kind of like when you call a taxi, the dispatcher doesn't tell you how far the taxi had to drive empty in order to pick you up.
Yes, from Chicago to New York, fine. This is from one airport in the San Francisco area to another airport in the San Francisco area. Give me the logistical reason for that.
Elon arrives at one airport. Someone else wants to use his jet, departing from a different airport (Elon isn't the only person who uses that aircraft). The plane is moved empty from one airport to the other.
The 5 stops on Caltrain between SFO and SJC is disingenuous.
Assuming starting at SFO, you need to take BART to Millbrae and then Caltrain to Santa Clara and then a bus to SJC. The whole thing would take like 1hr45min if you timed a baby bullet express train perfectly.
But yeah if drove or hired a driver you could get there in 40 min depending on traffic.
Because the passengers don't know where the aircraft is.
So for instance Musk might say "Gwynne Shotwell needs to fly to Austin on my jet on July 1." Shotwell says "I'll fly out of XXX airport". Then in June, Musk flies to YYY airport.
They aren't going to call Shotwell before her flight and say, "Turns out the plane just landed very close to you. Do you mind flying out of YYY instead to save us some fuel?" They simply reposition the plane.
It's justified because this is how professional pilots are expected to operate. Passengers are not supposed to deal with the logistics of their transportation.
For that matter, it's also how car-sharing is expected to operate. Imagine you took an Uber to your hotel, and the driver said "Hey, my next fare is two blocks from your hotel. So how about I drop you off there, it's just a five minute walk the rest of the way. Plus, it would save me from driving with no passenger for a few minutes, thus wasting fuel."
I think the vast majority of us would consider this unprofessional and respond, "No thanks, drive me all the way to my hotel". Which is why Uber drivers don't actually discuss their next fare with their current passenger.
I'm sure they have limos. Their limo driver is told, "Meet A at B street and bring them to XXX airport by Y pm."
It would be very unprofessional for the pilot to call the driver at the last minute and say, "Change of plans, now you bring them to ZZZ airport, it's a little further away which means you'll have to leave T minutes sooner". Depending on their schedule, A might not even be able to leave T minutes sooner.
We live in a society where staying on schedule is valued way more than reducing carbon emissions. Another thought experiment: you are 30 minutes late to work. Your boss demands an explanation. You say, "I have a very good explanation, today I decided to bike to work instead of drive". That's probably not going to be good enough. You are expected to emit CO2 whenever it's necessary to stay on schedule.