First, foreigners cannot buy land in Laos. But smart Chinese can work around the rule very easily, especially in very weak country like Laos and African countries where corruption is rampant.
Selling land for money is typical for what short-sighted and uneducated people do. They earn the money by selling land left to them for generations by their ancestors, they suddenly spend the money quickly and fight each other for the money and became even poorer than before. That's how a poor country became under the control of richer and more greedy people. Many Lao people in Laos are very primitive and have no notion of patriotism. The land doesn't belong to them because they did not buy it in the first place, it's left down from their ancestors, why bother, right?