It's pretty much like buying land. It's not like it's unethical to buy land if you have no plans of building an house on it, imho.

It's pretty much like claiming "new" land, to use an American analogy - you pay a small administrative fee, that's all.

Is it ethical to claim as much land as possible, for the sole purpose of selling it in the future to people who had the misfortune to come later? It's clearly legal, but it's also abuse of a common good.