Bit of everything, depending on the resolution, frequency, and region. If there's a decent frequency (~once per week) and perhaps meter resolution, you can do new site detection. The specifics you look for vary, but I can go into more detail if you'd like. If there's an oblique view rather than top down (preserving height information) and color accuracy, it could pretty directly compete with satellite in some of those use cases. There are also a lot of people at heritage agencies that have to monitor rather large areas for looters and other damage over time.

On the anthropology side, it might also be useful for looking at statistical information about populations/settlements that's difficult to collect other ways due to either the remoteness of the area and the frequency of other data sources. Things like nomadic migration patterns or land use in areas like Siberia / Mongolia, Myanmar, or northern Canada.