Problem is leaving at the airport, if they check and see your entry isn’t registered anywhere. Still could work if you plan on staying forever, hiking out, or flying private because only normies can do bad things and need to have their movements subject to scrutiny.
> flying private because only normies can do bad things and need to have their movements subject to scrutiny
You still go through customs when flying private.
Supposed to anyway.
Are they expecting every Cessna 172 travelling out-of-country to depart from one of their two international airports?
I have a feeling most of the way it happens is someone just says they are going to a border town and just ... don't stop. IF the pilot doesn't care about losing his license (i.e. they're being paid Do Kwon kind of money) and those on the flight manifest aren't returning, doesn't seem like there's much they'd be able to do.