This has very little to do with these folks being Americans, and very much to do with them being (I assume) of European origin. The peasants in that part of Mexico are direct and usually unmixed descendants of the various indigenous tribes that lived there before the Spanish arrived. They view Europeans and people of European origin as land stealing interlopers, and have for the past 484 years.
Any knowledgable wealthy Mexican would not to buy a rancho in Chiapas unless he also had the money to hire armed guards and the political clout to see that they had machine guns.
Lesson? Make sure you know what the h#&@ you are doing before you buy a bunch of "cheap" land in some foreign place and move there.