While the rarity of the Traveling Chocobo's several variants and exclusive prints significantly helps their desirability, the Traveling Chocobo's real power comes from how incredibly capable the new card is for landfall decks
You can also copy something and then hit the person with the highest life total
Well, you get to draw a card
Haunted Cloak is playable, too, depending on how well your creatures scale
Umaro, Raging Yeti (58 Lists) Oh yeah, it's time for a bit of chaos in your Commander game
Decks that want to play counters are almost always control decks, and control decks would much prefer to gain life rather than cause opponents to lose life, so all things being equal they would have preferred to play with Absorb but there were other considerations that forced most of them down the black road instead