The "land doesn't use resources" argument seems a bit out of nowhere, because we've been talking about people the whole time here - people's ownership of land. That's also why I mentioned valuable land and not large land. Land derives its value from proximity to other valuable things, and will be developed more densely the more desirable it is in that regard, putting proportional strain on public services and resources like utilities, roads, policing, etc. There's a clear cause and effect here in terms of land value and incentive to develop, and it's an advantageous route for taxation because it would be difficult to game.