Like, the first time you hear about it, you're like "HA! So funny. Let's go to Goodwill and spend $3.50 on some awful things we'll never wear again!" And then you go to the party, drink tons of rum-laced eggnog and 'misletoe punch,' puke all over your hideous sweater and throw it away.
While you may not remember cruising around the party blackout and topless, let me tell you something: skip the embroidered iridescent snowman next time. You'll undoubtedly get invited to at least two or three of these types of shindigs throughout the season, and after the first couple, it's really not as wacky and original of an idea as you may have previously thought. And, I guarantee you will smell vaguely of a thrift store the entire night, which is a pretty bizarre and off-putting musk.
A better use of those few bucks you'd drop on the sweater is to invest in a nice, convenient flask of Aristocrat gin. You know, the good stuff. And, extra points: it tastes like you're drinking Christmas trees and fire. Festive!