Note that when you "buy" land this is quite limited. For instance anything that happens sufficiently below it (e.g. subway tunnels, mining) or above it (airplanes), you have no say in it.

Similarly a state could say, you license (not buy) land for construction/agriculture etc. use. This license does not include extracting oil, which requires a separate license. The land remains property of the state, but for specific uses (e.g. housing) you have a guarantee that you can keep the license for 100 years and/or can renew it under similar conditions. This is for example what China does: https://en.wikipedia.org/wiki/Chinese_property_law