For the exact same reason we had/have people on this very forum that tried to shame people who refuse to wear masks. Who pull all but nearly worthless "proof" that masks work. Because some people, even normally sane people, get an idea in their head and it just has to work so they can blame others for their own fear and refusal to do the smart thing ... which is if you are that medically frail you have no business being any place else but in your home/bunker during any kind of infectious outbreak including anything normally associated with a vaccine such as flu and pneumonia.
Some people want other people to build their wall/bunker rather than do the necessary work themselves and take personal responsibility for themselves which means they wouldn't have other people to blame or complain about.
Some people want other people to build their wall/bunker rather than do the necessary work themselves and take personal responsibility for themselves which means they wouldn't have other people to blame or complain about.