Maybe a less Orwellian example....if I had access to all the Alexa and Google data from a particular area, street, or house, and I wanted to know which houses would be the best and least risk to rob, I'd find it a big help to see for how long they'd set their heating to 'away', or for how long it'd been since their Alexa last reported a command or question....
It has no access to my heating system nor anything else useful to such an enterprise. The only data it could derive from my living style, is the charger for my car going on and off, or my drive light, which happens whether I am home, or not.