I think Neobie's point is that why would you fly from Bangkok to Phuket and then continue to Koh Samui when you could have just got straight from BKK to Koh Samui?
For the same reasons I have to fly through Chicago or Denver to get to New York, even though I could go straight from LAX to NYC on a nonstop flight.
Of course we'd all love to fly nonstop whenever it's an option, but often times we don't for any or all of the above reasons. Production doesn't have an unlimited budget and the nonstop flights from Phuket to Ko Samui are very cheap ($89).
Here's an example to illustrate my point. Flight search for a one way ticket from Jakarta to Ko Samui departing later this week:
$664 is cheapest option, and all flights with this price are via Phuket
$995 is the price to fly through Bangkok (!!) and this itinerary would be ~6.5 hours, only around two hours shorter than the cheaper option through Phuket (~8.5 hours)
I think if WRP could save $1000 by having a team and one production person take the first option, it makes perfect sense.
That's odd ?
I get a routing from Jakarta to BKK to Koh Sumui for $974 that looks like this
Thai Airways – Flight 434 3h 30m
Take-off Fri 12:35p CGK Jakarta, Indonesia
Landing Fri 4:05p BKK Bangkok, Thailand
Coach | Airbus A330-300 (Wide-body Jet) | 3h 30m | 1444 miles
Connection BKK Bangkok, Thailand 4h 55m
Bangkok Airways – Flight 199 1h 00m
Take-off Fri 9:00p BKK Bangkok, Thailand
Landing Fri 10:00p USM Ko Samui, Thailand
Coach | Airbus A319 (Narrow-body Jet) | 1h 00m
And the only routes that do include Phuket also happen to go through KUL and those are coming in at $664. They look like this:
Malaysia Airlines – Flight 710 2h 00m
Take-off Fri 11:10a CGK Jakarta, Indonesia
Landing Fri 2:10p KUL Sepang, Malaysia
Coach | Boeing 737-800 (Narrow-body Jet) | 2h 00m
Connection KUL Sepang, Malaysia
Malaysia Airlines – Flight 790 1h 15m
Take-off Fri 5:10p KUL Sepang, Malaysia
Landing Fri 5:25p HKT Phuket, Thailand
Coach | Boeing 737-400 (Narrow-body Jet) | 1h 15m
Connection HKT Phuket, Thailand
Bangkok Airways – Flight 258 0h 55m
Take-off Fri 7:05p HKT Phuket, Thailand
Landing Fri 8:00p USM Ko Samui, Thailand
Coach | Aerospatiale/Alenia ATR 72 (Turbo-prop Plane) | 0h 55m
But since we know the racers were spotted on a flight from BKK and not from KUL we can conlude that they were not continuing to Koh Sumui.