Every year, every award show has people, movies, television shows, and music that is snubbed. Also, who or what is snubbed is subjective. Ask one hundred people who or what should be nominated and you will get one hundred different answers. There are only so many nominations to go around and you can't nominate everyone. The ceremony would last even longer!
David Bowie's 'Blackstar' was a notable snub this year given the wide outpouring of grief following the iconic star's death earlier this year. It is also surprising that Kanye West was not nominated in the major categories given the huge amount of critical acclaim and social media hype his album received.
Too often, the Grammy awards don't go to the person who is the best artist. Too often, they go to the artist that is willing to do the craziest thing on stage. Or, they go to the artist that does the craziest dancing, or makes the most politically outrageous comments in public. Meghan Trainor should get more recognition, among others.
Having looked over the nominations reasonably well there weren't any big snubs that I could immediately think of. Although I'm sure others will disagree, especially amongst the artists themselves. For example although there were some nice chart friendly songs on Bieber's "Purpose" album I'm sure lots will feel he shouldn't have been nominated because other albums are a demonstration of much higher talent by the creators.