Because of their rarity, you may not get a second chance to pick one of these up in a draft
Stuff like Snuff Out or Dismember are already heavily played cards, but here, you get to draw a card from them because you lost 4 life, and you also get to drain your opponents for 2 life, offsetting your life loss
We also have the classes themselves shown off in the entirety of the set thanks to the number of Black Mages, Warriors, Red Mages, etc in the entirety of the series
Its been banned in Commander since 2007, and it doesnt see much play in the other formats in which it could, Legacy and Vintage
Combine this with the fact Frodo can be out as early as turn two with the right mana and you've got a hobbit that will keep your hand full and the Ring whispering in your ear
In many ways, Doughnut is the logical conclusion in the Wizards quest for an integrated finale to the Magic year, and crucially its a set that you have to buy. In terms of Standard, Doughnuts 50-60 rares may not make a startling impact, but you have to remember that it services not one but two Block Constructed formats