The lower tech approach means you can park a van in my driveway and probably pick up the signal but that's a lot harder (and more obvious) than scanning an IP range from anywhere in world and finding vulnerable devices.
[1] https://www.amazon.com/Foscam-FBM3501-Wireless-Digital-Monit...
Still pretty weird seeing the constant log entries trying to reach a couple servers - I've been doing traffic capture since I'd like to see what it's trying to do. One is obviously the plug-n-play stuff, but it's crazy that those packets apparently get broadcast outside the network (? - I haven't really looked into how that PnP IP/port is handled but it's getting caught at my firewall).
With Nest, you have to use their "cloud" for it to be fully functional, which to me makes it a no-go for anybody like you who is actually concerned with his/her security/privacy.
The most popular IP camera on Amazon is a Chinese camera gets your Wifi password through their app via the "cloud". Fuck that.
And? What does it matter that someone has a password that's only good for about 100 metres around your house?
Of all the passwords I have, my wifi password is the one I care least about.
I'd be more worried about what the app itself is doing on my phone - I caught one attempting to update outside of the Play Store. No thanks.
If it is Chinese-made, that might just be because the Play Store is blocked by the Great Firewall. Apps in China need to use some other way to update.