Claim is that "scarcity is the presence of choice." Claim is that something is scarce when it can be put to one use, or another use, but not both uses. Hence, alternative uses. So yes, when something is scarce, have to make choice. And point of this article is to show that scarcity is no question of desire or want, or rarity or limitedness of thing, but only where choice exists, so does scarcity, and vice versa.