Postulate: Hinterlands cards make Trash-for-benefit cards better.
Hinterlands seems to include a plethora of cards that allow you to increase deck-size overall faster than the usual "buy 1 card per turn" paradigm (cards that we know of now that can do that: Border Village, Trader, Develop, Ill Gotten Gains, and Nomad Camp gives you +buy). Trader and Develop in particular are going to result in a lot of mediocre cards (Silvers, $3s, and $2s), that will be good fuel for, say, Apprentices or other TfB. But, hey, while you might ordinarily flinch at feeding a $6 card into a TfB, why not a $6 Village that you got by overpaying for a $5 Action that you REALLY wanted? Okay, the Coppers from IGG are unlikely to result in wildly useful TfB, but maybe if you're playing a Hinterlands heavy deck, you traded them for Silvers.
Develop being both TfB and deck-size increasing is, if my postulate is correct, slightly insane.