I was absolutely amazed when I saw motor cyclists in Thailand not wearing helmets. I mean in Taiwan some motor cyclists drive stupidly crazy squeezing in between vehicles, going through red lights, and zooming ahead when the car on the left signal to turn right. Many don't wear a helmet when driving in the rural areas and villages (why????) but at least when they're in the city they put a helmet on. I was gobsmacked to see people in Bangkok city not wearing a helmet.
The "It won't happen to me" mentaility is what gets people killed sadly
RE: The day a person died right in front of me: True story but a bit graphic