Based on the lore of the literary classic, it was originally supposed to be a standalone game , and was changed during the design process to integrate with the existing cards
Moving the card from the stack to the graveyard (replaced to moving to the hand by the effect) happens at the last stage of resolving the spell
Is there a graveyard recursion player at the table and you know Torment of Hailfire is about to be recast
Sure, it isnt literally a multicolor land that enters the battlefield tapped, but in terms of functionality, it allows its caster to continue developing, yet forces them to sink a single mana into the fixing its providing
Stay safe, and conquer if you want to eat
There are several reasons for this, including the fact that they were the first to be released and therefore more difficult to find and collect, as well as the fact that they were more popular in their day than many of today's most valuable Pokemon cards (which have only come into existence within the past several years)