I can't talk about China, but this scheme would probably work in a lot of places in Japan. I used to ride my ~$700 hybrid bike to the train station a lot. At first I locked it, but then I noticed that mine was the only locked bike. I ended up leaving it unlocked. Kept that up for 5 years or so and my bike never got stolen (admittedly I live in the country side -- not sure how successful that would be in a big city).

When I lived in the UK and Canada, I would never dream of leaving my bike unlocked. Even locked, I've had bikes stolen. Once, I locked my bike to a bike rack and they stole the whole bike rack (must have been a chore!). Most of the time, they will deflate your tyres in hopes that you leave the bike there overnight so that they will have some time to cut off the lock in peace.

Anyway, it's just cultural. I suspect that's hard to believe (it would have been hard for me to believe before I left Canada). In each culture there's a lot of stuff that's good and a lot of stuff that's not so good. People really do behave differently, but I've travelled enough to know that one culture isn't really appreciably better than another -- just different.

Many reasons.. but it ultimately comes to one thing, Cops do not give hoot to bike theft, so the rist-reward in bike theft is favorable.

Because a lot more things affect crime than just socio-economic status.

In the case of the US per capita GDP just means that we are a country containing many rich people, not a rich country. Income inequality is extreme. When the government or private industry refuses to redistribute money downward, poor people will just take it.