That I understand, it's their basic marketing. What I don't understand is how that can work.

Aren't we also supposed to be adults? aka people able to consider the cost/consequences of our choices and of... free gifts?

I'm not a geek, but the day those gizmo started promoting "easy access to a live feed of your pet at home" what I read was "easy access to (...) your (...) home by a technology I don't control (nor really understand)". To non-geek me, it was a bit like give my home keys to some smiling random stranger. Sure, e may be a nice guy that will only use the key when I want him to. But he may also not be. And I'm old enough to not be willing to trust some random stranger, even one with a nice smile.