So the term post-apocalyptic thrown around a lot describing this line. I realize that some on the forum fully embrace this term in terms of creating a style.
So I decided to do some digging on the designers. It's a brother-sister duo. Though they did some pieces for the Hunger Games movies, currently they cite more than once references to nature and the outdoors for their inspiration. Also not necessarily futuristic.

Fall 2014

Interview for spring/summer 2015

Interview for fall 2015 show

But in the end it is what the consumer sees and wants which can vary greatly from the designer's intent.

ETA I've seen some scuttle that the whole dystopian genre in literature and movies is played out.