I am not aware of a TV that requires internet access to show a picture, but I haven't looked in a long time. I don't think a TV will try to hack nearby networks, but it is possible that it strongly suggests you to connect to the internet, for example by showing nag screens, locking out essential features, or fixing breaking bugs that should never have been allowed to ship.
What I meant that you can buy a smart TV and take advantage of the lower prices but you should make sure that you can actually use the TV without a network connection (and yes, that it doesn't try to hack your wifi).
Are you sure that’s always true?
What about smart TVs that seek out open wifi networks or try to access the internet via HDMI?
The problem with smart TVs is that you loose control of what they’re actually doing.
i.e. LG smart TVs searching your network for media and sending a log back to… somewhere.
Or Samsung smart TVs sending hashed images of what you’re watching back to… somewhere.
This happens regardless of if you’re using the smart features or not.