The thing I mentioned about statistics applies. Crimes are underreported in Malaysia. I get the impression they're overreported in the US.
Sometimes it's fairly innocent e.g. a lot of people feel the police are the last resort. People are known to "settle" accidents. Even burglaries; you can have a gentleman's agreement that the robbers will inform all their friends that this house has been robbed and there's nothing left to take, while the victims agree not to tell the cops. Or say, a teenager caught for drugs may not be reported, because the punishment is death. They'll just be expelled, beat up, or let off with a warning.