A lot of the Transaero pilots were trained onto the Boeings by BA some years ago, so their standards will be good!
However, I think most people wanted to get back to their jobs (if they still had them), and getting out of Thailand by any other means wasn't easy. Paradise it may be when everything's running OK, but like all such places, the system breaks down completely when things go wrong.
There were other means of transport! It comes to decision time- do you try and get out by your own means, or sit on your arse for as long as it takes assuming it will end anyday and in the meantime scream for British government rescue? People travel abroad now, and many of them are naive, regarding HMG as some sort of rescue organisation if anything goes wrong. And things did not break down in Thailand. Pat Pong was functioning, the street markets were functioning, power, water and public transport were working. The system did not 'break down'! Brits fell to pieces when they started missing X Factor and 'Enders!