You don't need "social awareness" to explain any of your observations:

1) Low income inequality / strong welfare system 2) This is actually a counter example. Nothing more socially offensive than second hand smoke. 3) Trash cans disappeared from the streets of Tokyo shortly after the sarin gas subway attack by Aum Shinrikyo in 1995, and they've never reappeared.

But even without trash cans, Japanese people don't litter, ever. In contrast, Berlin, where I currently live, has lots of trash cans but the streets are full of litter.

Berlin doesn't get cleaned enough by the city. Yesterday it was still covered in fireworks and empty wine bottles from New Year's Eve. The only reason it looks clean today is because it's covered in snow.

If it were cleaned more regularly people wouldn't litter so much. (Not a defence of people who litter, and it's the one thing I hate most about living here.)

Here is another example:

One time last year I had to stay overnight in Japan to reach a connecting flight. The airport allowed people to sleep on the benches (very comfortable with no arm rests), and a police man stands there all night and watches over everyone to keep them and their belongings safe.

To top it all off, there is a sign addressed to people sleeping there that at 3 AM the airport personnel need to polish the floors and they apologize for the noise!

(This was at the old Haneda airport near Tokyo)

Similar experience. I was in a Ryokan in Kyoto where some workers were about to repair some fittings in the street and make some noise. We were given a leaflet in English apologising for the noise made and the next day when we got out the supervisor was ready with a candy and a small toy for our daughter.

> Garbage cans are hard to find too and everyone just carries their trash with them.

I was told this is a relic of the sarin gas attacks in the Tokyo subway.