I know that Japan is a lot more implicit in enforcing its culture. But it is not a country that runs on honor alone. It has police, it has prisons, it has courts. The lawyer comparison doesn't tell me much because the US is a very litigious country in ways that go far beyond individual criminal law.

Besides, the implication you made is that a lot of the actions people don't like are already illegal, just not tightly enforced. Especially if you say Americans would shoot the perpetrators on the spot.

Even if they wanted to protect their status quo, they could only apply stricter requirements on residents who haven't received their citizenship yet. Law-abiding immigrants in many countries are used to having to clear higher bars than locals. But at least in this case this would be equitable, only punishing the people who actually do something wrong instead of everyone.