If posters are not willing to read as far as the first sentence below the headline on the article's page, why should they be invited to discuss the article with those of us who have made the effort to read it?
Well, they could conceivably watch as you enter/exit your home, but if you have Alexa already then I would think they could infer from silence or lack-thereof whether the home is occupied.
Alexa doesn't open any connection to Amazon servers until you say the hotword 'Alexa'.
One could still infer from a lack of 'Alexa' hotword prompts over a span of time whether the home was occupied I reckon.
Or Bluetooth connections if you can use it as a speaker. Or the presence of other devices on the WIFI. There's a few ways you can passively detect human presence, I think.
That kinda logic doesn't work. Just because someone doesn't use Alexa for hours doesn't mean they aren't home. It happens every night.
I will elaborate further: inspect usage trends of Alexa to determine anomalies, i.e. times of no usage in the day when the owner isn't home.
They have a version of the Amazon Echo that has a camera for video calls. Its called the Amazon Echo Show.
...And what about people who use their garage door for main entry/exit?
All of those amazon echo products are watching you.