Maybe they did. I would not tell anybody if I got a picture of it. I also live not to far from an Air Force base. They are always doing stuff. No one really pays any attention to it. Practice, etc.
Imagine how many fisherman are out in the Puget Sound early in the morning, somebody would say something - especially when the media got ahold of it and the lame-ass helicopter story needed to be spread.
The only thing close to practice missile launches is from Joint Base Lewis McChord which did some testing in 2016 to see how much noise was created.
http://www.thenewstribune.com/news/local/military/article55498255.html
Joint Base Lewis-McChord plans to proceed with a three-day artillery test in March that will help determine whether the Army can practice firing rockets that have the potential to create sonic booms in the South Sound area.
Imagine the noise launching an ICBM/Satellite Killer from Puget Sound's busy shipping lanes would make. The BOOM would get some attention, I'm sure.
I know well the sound of freedom, and how it becomes background - but this would have been an extraordinary event.