Evey Hammond, I just got a price for a non-stop flight Kuala Lumpur to Amsterdam on a Malaysia 777, departing 11;59 PM on March 15 : $780.
So why fly via Beijing? At a higher price?
To avoid the requirement for a Chinese visa. If using a stolen passport the traveler is unlikely to want to drop it off at the local Chinese Embassy for 24-48 hours then return to collect it in case they check its legitimacy. As noted earlier if transiting China for up to 72 hrs you don't need a China Visa.
Question is, were these miscreants anything to do with the disappearance of MH370? Or were they just criminals looking to obfuscate anyone trying to track them?
Hell, it could have been a couple of Jason Bourne types...