The costume's original coin price was 1,000, but the game makers changed it to 10 coins to help all players unlock it faster.
Holiday Sweater's old power (in the jelly lab versions) was a Free Revive in Rush Avoiding courses.
Since abilities came in the game, all tasks that required picking up power-ups a number of times were changed into using their respective abilities a number of times. As a result, Holiday Sweater's utility, as well as all costumes that increase chances of certain power-up pick-ups became redundant. Instead, new costumes appear, giving shorter ability-charge.