People probably want that Level 3 Auction badge (from winning an auction).
As for $571 on a holiday profile picture...I have a feeling money is a very, very small concern for some of the high bidders. It's really just gambling for them with little or nothing to lose.
I honestly believe it's Valve taking advantage of people with a certain level of OCD for collecting. I know I have it to an extent. Not here (thanks God) but in certain places I'll have the feeling if I miss it I'll never have the chance again.
- Foxhack likes this