You're suggesting that my TV would connect to a random open WiFi, it sounds far fetched
As a thought exercise ask yourself would you notice if any of your closed WiFi-enabled hw scanned for APs and occasionally phoned home, if it didn't go out of its way to inform you of this? What would prevent the vendor from doing so?
At some point it will potentially connect to people walking by on the street (Amazon Sidewalk). For now they haven't hooked Fire TVs into it.