I see a smart meter as quite similar in principle to an Alexa, which we will also most definitely not ever be having in our house.
If you're frail, disabled or otherwise have a genuine need for one to help you in your everyday life, then fantastic.
If you don't physically need one but just like the spontaneity it brings you in return for having something permanently monitoring your household and transmitting data to the government, companies, hackers and anybody, anywhere in the world, with the technology and skill to harvest it and exploit it in their dealings with you (whether you've actively given permission, unwittingly given permission or have not and maybe would not ever give them permission) - then great, crack on; entirely your free choice to make.
Personally, we just use a computer and type in what we want from the internet. It only 'wakes up' and responds when its own buttons are touched, which, unlike speaking normally to each other in our home, is something that's easy to avoid unless you specifically want to use it.
No offence to you, OP, but your question as to why people who don't want smart meters are so dumb just instantly makes me think of these hapless souls you see in the media (especially the local papers), who've done something unbelievably and so obviously (to most people) foolish and then run to the paper to 'warn others' that, although nobody would ever dream it to be the case, sitting on the far end of the branch of a tree which you're sawing off next to the trunk is in fact, very dangerous - everybody should learn the lesson from them and not have to find out the hard way as 'it's an easy mistake that ANYBODY could make'.