Treasure hunt as defined by NPD is the process of consumers bargain hunting. It might be discounted pricing on items or looking for substitute pre-owned products.
Discounted items used to be seen in the retail trade as the preserve of older consumers alongside couponing. But as empirical experience going along to discount outlets show bargain hunters reach across social classes, income levels and age groups. Discounted products accounted for 3 percent growth in retail, even while retail declined by 1 percent overall in the last quarter.
As for pre-owned goods, whilst NPD thinks that this is a millennial trait – vintage clothing stores, crate digging for records and and eBay are evidence that this trait isn’t new.
Admittedly the motivation that they are ascribing to vintage shopping by millennials and gen-z adds environmental aspects to vintage consumption. (Though is probably quality aspects as well as apparel globalisation and fast fashion have gone hand-in-hand in the demand for heirloom design).