@alex We can’t do it without a passport because we’re so good. We are the apex predators, and need some level of restraint.
You might think it’s dumb since for you it’s just a formality and you aren’t planning on doing anything (substantively) illegal in your host country, so the population doesn’t need to be protected from you.
But they definitely need to be protected from some people, who are predators that don’t intend to abide by the host country’s laws.