If you were to play devil's advocate to your own question then what would it sound like? I personally haven't bought any silver yet, and I agree that it would be cooler to earn/grind for these emotes in-game. However, if I had bought some silver I would have justified it by wanting to be different than other people in the player base. It would be partially to see the animation I thought was cool and partially to be set-apart from other players.