//Who is worried?//
Perhaps “worried” isn’t the right term. So why did you say that Mrs Cheese should “…stay away from crowded areas and places where the public gather.” Why does it concern you what others do?
//The elected leaders of those countries obviously feel differently
Why would that be I wonder ?//
“Elected leaders” always take it on themselves to “do something”. It makes them feel good. In the UK compulsory vaccination is unlawful. If Parliament wants to change that it is entitled to do so. Good luck to them with getting that through both Houses and good luck with enforcing it should they ever manage to do so. Until then, it is a matter of personal choice. So long as it is, to deny people, who have exercised their choice in a way of which you don’t seem to approve, access to certain places is hypocritical. Get the law on vaccinations changed or do not discriminate against those who have exercised the choice that is currently available to them under the law.
//Some see it as their duty not to be or want to be difficult for the sake of it//
There all sorts or reasons why people have declined the vaccine. Some of them are sound reasons (I have a nephew who has a particularly sound reason which I won’t go into here). Others are frivolous or, in many cases, simply absurd. But the fact is they have a choice. As it happens I agree with you entirely – everybody should be vaccinated unless they have a very sound medical reason for not doing so and I think people who don’t do so without good reason are just plain bonkers. But I defend their right to make their choice, however bonkers they may seem.
Prior to the pandemic this country was not an authoritarian state. People have choices over most aspects of their lives. The legislation that keeps society in check is mainly prohibitive – you mustn’t steal things; you mustn’t break the speed limit; you mustn’t assault anyone. Very little criminal legislation Is prescriptive, apart from perhaps you must pay your taxes. We don’t have legislation which compels people towards certain behaviour and as soon as we do the genie will be well and truly out of the bottle.