[TeMPOraL]

> Ever heard the rule, "pack it in, pack it out"?

Yeah, in religious congregations of a particularly controlling near-Christian denomination.

> Or "leave the campground better than you left it"?

Yeah, in movies. I hear that Boy Scouts actually adhere to that rule.

I've only ever seen these two rules applied in a pretty top-down fashion as tight-knit community rules. It's not something I've seen random people invoking in generic situations, so I'm not sure if it scales to the level of a city or a country.

[Reedx]

It's just like any other cultural norm. And Japan shows that it can scale.

Really, it's just a simple common courtesy. And I say this as an atheist non-Boy Scout.

[TeMPOraL]

If it's "just like any other cultural norm", then we still have a problem - as I wrote upthread and elsewhere, cultural norms are extremely difficult to create or change. You're much better off seeking different points of intervention... like making producers of (what becomes) trash involved and primarily responsible for reducing the amount of litter.