^^^ In answer to your earlier post's question, while no expert on Indonesians, I did live there for four years and am married to one...
In general, and yes, generalisations are very dangerous, but there is usually some truth in them, it seems to be the case that if something has not happened previously to an Indonesian, they don't see that it could. Hence they cram 5 people on a motorcycle and weave through the traffic to see Granny on a Sunday (along with 10m others in Jakarta!). I watched a guy on a tower crane on a building site over Jl Sudirman clamber along the arm and start bashing a recalicitrant bit of machinery with a hammer, no apparant safety equipment other than hanging on manually. I have seen roadworkers swinging pickaxes and shovels while wearing flipflops. Amazing place.
As to why they are flying through thunderstorms, Indonesia is still largely a society where you do what your boss says.