That's exactly what the Facebook app is on a mobile phone, though. Has access to the microphone to listen whenever it wants (even if it doesn't do it, it has access). Is always on, not just in your home but everywhere you go. Knows who you talk to and where you are and how long you spend there and often what you're doing quite exactly to the details.

There's not much difference between having the Facebook app installed on your phone and this device, in terms of creepiness and data collection capability. Probably their smartphone app creeps me out more, actually.