They enable big turns and protect fragile commanders so players are able to have more fun doing their thing, and printing them in precons means the average player will have access to this vital effect
Borderless foil: Around $22 Foil: $22 Non-foil borderless: $15 Regular: $19 Minsc & Boo, Timeless Heroes Minsc and Boo first made their appearance within AFR , on a legendary card with Boo pulling sidekick status
Although the wait can be a slight restriction, Necropotence effectively trades 1 life for 1 draw as often as its player would like
This doesn't mean you should buy the decks to profitthat's unlikely to work, since Wizards upped the supply of Commander decks after the True-Name Nemesis debaclebut it does mean that a lot of expensive, powerful, and fun casual cards are going to get cheaperway, way cheaper
The gyroscopic foil effect is a close second, though