Wild Guess

Loot effects are red and black's compensation for the colors that draw cards outright, and this is the rawest version of the bargain: two cards drawn for two red mana, with one card from your hand thrown in as part of the price. The transaction is strictly card-neutral, you spend the spell plus the discard and you draw two, so what you actually buy is selection and velocity rather than raw advantage. The discard's status as an additional cost is the load-bearing detail. Because it locks in before the spell resolves, you are committing the card to the graveyard with no information about what you are about to draw, which only matters because of where that card lands. In decks that treat the graveyard as a resource, the discard is upside rather than tax: a flashback spell you can recast, a creature with a recursion clause, fuel for delve or threshold. Stripped of those payoffs it is a plain dig that turns one card in hand into a fresh pair, fine but unremarkable. The double-red cost is the other constraint worth noting; it shuts out the three-color piles that want this kind of digging most, keeping it in mono-red and committed red shells rather than the splash decks that would otherwise grab any two-mana draw-two on offer.