Like someone else has mentioned you're more likely to find them in corner shops and in the discount stores like Home Bargains and B&M.
But in my opinion they're probably not readily available because they're just not very popular. Gummy Bears are a bit boring and bland compared to the other sweets available.
Growing up I'd sometimes get a 10p mix up from the corner shop after school and there's no way I'd have wasted a penny on a gummy bear when I could have gotten a giant strawberry, a ufo, a black jack, a fruit salad, a fried egg, or best of all a foam shrimp/banana.
Oh this is absolutely true, even limited to candy with gummy textures there are so many good options -- Trolli worms, Starburst gummies, Sour Patch, Nerds clusters, Mike & Ike, Sweetarts gummies.
The thing these all pretty much have in common is incorporating a more sour/acidic taste to varying degrees so that is probably a turn-off for some but it's hard to argue with the result being incredibly flavorful.
There are several major products that are Kosher or Halal despite the biggest market being the West. Snapple Ice Tea is a good example of a Kosher product.
The only rationale I can think of is if you are going to mass produce some food product, better to start with something you can sell everywhere, than start with a Western version and then change (or add to) your product line later.
There are a lot of products that are by default Kosher and Halal and just added the sticker on top for advertising. What could you add to Ice Tea to make it not kosher other than preparing it in non-kosher equipment (which is possible, but unlikely in the case of ice tea)
As for the number of vegetarians and vegans, the UK reports 11% who live at least vegetarian or stricter per [1].
Unfortunately I haven't been able to find vegetarianism and religion correlations for the UK, but in any case it's safe to assume that anything between 11 and 19% of the UK's population are in one way or another following ethics that refuse gelatine-based products. That is not "nobody" at all.
[1] https://www.food.gov.uk/sites/default/files/media/document/f...
A more useful study "puts the size of the vegan population at about 2-3% and the vegetarian population at about 5-7%" [1].
From the article, it appears that only 2% of vegans, and 3% of vegetarians surveyed did so for religious reasons.
[1] https://yougov.co.uk/topics/lifestyle/articles-reports/2022/...
That doesn't even come close to being a safe assumption; it's wildly overoptimistic.
Kind of like claiming that, since Buddhists are forbidden to kill insects, and almost everyone in Thailand is Buddhist, killing insects is rare in Thailand.
We already know that most vegetarians are happy to eat meat. Compare https://academic.oup.com/ajcn/article/78/3/626S/4690004 , finding that two out of three self-described vegetarians had eaten meat within the past one day. They are even less likely to be worried about incidental animal products in candy.
Also Haribo bears are available everywhere. This whole thread is very odd.