"They are also attached to the places, and do not wish to leave" That's kind of a distorted way to look at it. People do leave, and then they aren't included i

"They are also attached to the places, and do not wish to leave" That's kind of a distorted way to look at it. People do leave, and then they aren't included in the population that's under the microscope. So the remainder is always being distilled down, no matter how bad things get, until the outside world decides they can be ignored. Same thing with farmers in the 20th century.