It's not like that yet in the UK unless they're specifically guide dogs which are virtually only for the blind, unfortunately it's still up to the establishment at the moment for autistic people and anyone else who need an animal for other support when it's not directly classed as a guide dog, unless the law changes and I wish it would. I know it's better in the USA.
I don't know much about the USA, as I'm from Canada, but I think it's similar to here.
That really sucks that only guide dogs are exempted, I hope the laws change in the UK, too.