I see your point, but it's conflating a couple of issues. The comment I'm responding to was saying that a smartphone isn't a spy device because it doesn't listen to you, and the Echo does. My point is they're both spy devices, just opaquely crippled to varying degrees.
To the other point, I'm not entirely sure I'm comfortable with the patents, but it's at least an Echo simply gleaning more from a voluntary engagement with it. I think the general feeling is an Echo is "spying" when it engages itself to listen to your home.
Of course, I have no way to know if my echo is doing that, or if it were to start, and it's out of my hands to prevent it. The same with a smartphone.
If Amazon wanted to spy, probably a smart tactic would be to deliberately "flaw" the wake word recognition such that it could plausibly be a bug, but the result is activating very often randomly. They already kind of do that, it would just need to be more frequent.