Plenty of airports do not have controlled airspace. I've been to at least one where the local frequency was played on a loudspeaker on the ground so that people

Plenty of airports do not have controlled airspace. I've been to at least one where the local frequency was played on a loudspeaker on the ground so that people on the runway knew when a plane was coming in for a landing. The pilot still should communicate what they are doing, but they don't need approval to land.