And to make matters worse, even people who aren't directly taught may see others doing it frequently enough that "monkey see, monkey do" comes into effect. Which means more people see it, and.... If the percentage of people "acting differently" from the group norm (eg, the norm of putting your own trash in the bin) is very low, then they stand out as "doing it wrong" and others are unlikely to follow them (or may even correct them). But if enough people are "acting differently" -- eg, the trash is strewn over the ground -- then that differently can become the new norm.

Sadly some of these things are very effective for the individual if they're the only one doing it, but terrible for society if everyone is doing it. Which makes it more likely to snowball.

Ewen