Because they didn't buy the fridge, their landlord did.
Because the fridge is installed at a workplace, or community centre, or other location at which the individual has no effective choice.
Because there are no new fridges with other desired features which don't have screens.
Because, at some future date, absent legislation or crushing litigation, no non-screen, ad-free fridges exist.
Substitute for "fridge" and "ads" any of number of other consumer / general appliances: stoves, washing machines, dishwashers, phones, televisions, thermostats, doorbells, petrol pumps, etc., or features: cameras, microphones, speakers, iris scanners, thumbprint readers, facial recognition, etc., etc.
It wasn’t possible - there was literally no TV available that didn’t have a small computer built in to connect to the internet and send all my usage data somewhere.
I probably have to find a second hand one somewhere or just continue to live without one.
Not saying that it’s the same with fridges - but who knows a few years down the line it might be…
I have yet to run into a TV that doesn't work entirely offline at any pricepoint
The tv also has a microprocessor to upscale/decode content. Most tvs also have the ability to connect to a variety of sound systems through Bluetooth.
If your concern is additional cost for the bundled features, I believe the ads subsidize and offset the cost. (I'm not pro ad. Again, I do not connect my tv to the Internet, but let's not reject the benefits entirely).
"Non smart" TVs are prohibitively expensive in my experience. They are large format monitors. You can also consider a projector.