Not only can you repair and vendor items on this mount, but you can also purchase food that’s useful for levels up to 80.
Raid groups always had to rely on someone having a repair bot in their group if they needed to repair, or they had to ask their Warlocks really nicely to make a summoning stone so they could Hearthstone out and get repaired. This was a really exciting addition, as nothing like this had been seen before. The Reins of the Traveler’s Tundra Mammoth was the first vendor mount to be added to the game back in Wrath of the Lich King.