For a BST to even exist, there needs to be new purchases from time to time. 
I have no problem grabbing stuff on the used market, but I also believe in buying new when I can. It keeps any number of people employed and in business. BST only helps the yoyo market in that by feeding the addiction and giving people the opportunity to be active consumers of yoyos, they may continue to buy new yoyos periodically.
Most expensive purchase: C3 Krown @ $160