It releases weekly because Netflix get it outside the US at the same time AMC air it on television.
I think Netflix should move to a weekly model for their content but they haven't done this.
But then there is even less left that I really want from Netflix. This also explains why this show is so much better than the other stuff on Netflix.
BTW if you don't mind me asking.. why would you prefer a weekly model as a consumer? The only reason I can come up with is that people fear to read/hear spoilers from other who are "faster". Is there something else?