So lately I've realized that there has been massive amounts of crowns circulated in SK. Here is a list of crown sinks built in game to "reduce" the amount of crowns in the game:

1) Whenever you use the elevators in the arcade (no one does this anymore though)
2) Whenever you put up an item in the AH, 10% of the buy price or bid price is taken.
3) Whenever you put up an item and you don't sell it successfully in the AH, the listing fee is not refunded.
4) Whenever you craft something, it requires some crowns.
5) Whenever you go but something, anything from vendors, although no one does this.
6) Whenever you pay for your guild hall's upkeep.
7) Whenever you are purchasing additional rooms for your guild hall
8) Whenever you buy a monster pocket from Nonna (dunno where she is though)
9) Whenever you buy candy during the Halloween event, the Dark Harvest (you'll have to wait until October)
10) Whenever you get the Chroma in the prize wheel and it takes some money (probably has never happened to anyone)

If you think that you have more ideas, post them. Seriously though OOO, you better come up with better ways to separate people form their crowns.