Classic packs are dust fodder with MAAAAAAYBE a chance to get one legendary you still haven't got
Meanwhile, Ungoro packs are going to give you cards that you FOR SURE haven't got yet
In a couple weeks you're going to want as many Ungoro packs as you can get, to better your chances of getting cards to make you competitive in the new meta. And Blizz is giving you packs from the new expansion FOR FREE.
I cannot fathom why you would complain about this.