There could be a number of reasons for this, and those reasons could vary from country to country. Here in the United States, I have done all of my teaching in rural schools. I enjoy it a lot because of the culture of those schools.
In rural schools, things are still less omplicated than they are in urban schools. In urban schools where friends and family members of mine teach, there are all sorts of rules and regulations. Teachers always have to worry a great deal about what they say and how they act. They are often also subjected to the orders of a large bureaucracy in their school district. They have little autonomy.
My experience in small schools has been very different. Teachers are much more free to do things the way they want to do them. They do not have to worry that someone is watching everything they say, just waiting to report them for saying the wrong thing. It seems like a much less stressful envrionment in which to teach.
Of course, there are problems with teaching at a rural school, but these are the major benefits that I have experienced.