I haven’t read through all 23 pages of this thread but:
I am a guide dog owner. As such my dog is allowed everywhere.
And in my experience people with allergies fall into two groups. The ones who have allergies, who manage their allergies, and who will have a reasonable conversation if my dog enters their space to the extent it could trigger a reaction. It’s perfectly reasonable to accommodate those to the degree of moving further away from them/not letting the dog in their space, and as a rule these are reasonable people who wouldn’t be shouting demands and expectations because they, like me, are just getting on with their lives.
And then there is a sub-set of people with allergies who will demand, shout, insist, throw out emotive language, and who most definitely are not reasonable people and as such I have no inclination to accommodate them.
I was in a shop a couple of years ago and the woman standing next to me was there for about five minutes, chatting to the bloke behind the counter, making her selection etc. Then his colleague came to talk to me, I bought what I wanted and turned to leave, at which point she subjected me to a mouthful of abuse about how my dog shouldn’t be allowed in the shop, how she had such severe allergies and how she might die now. Thing is, she was stood next to me for the entire time. There’s no way on earth she couldn’t have seen my dog. If she’d said at the time that she had allergies I would have stood further away (allergies to the extent that you can’t be in the same room as a dog are extremely rare so it would have been possible for her to not be in any contact with the dog). But given she shouted, screeched and made accusations just made her look like a twat instead of a person who was genuinely struggling.
Sometimes it’s about compromise. If I was in a cafe and a child came in and was having a meltdown because my dog was lying quietly on the floor then I would have no reason to leave IMO. But I’ve been into a shop, walked into an isle and a child has clearly reacted to my dog at which point I’ve just walked out of that isle and down the next one so that dog doesn’t scare child is a perfect compromise.
Taxi’s are obliged by law to carry guide dogs. it is in fact a criminal offence to refuse them except in the instance of allergies, and if a taxi driver has an allergy they are obliged by law to carry and display an allergy exemption certificate. However I’ve had taxi drivers say they’re scared of dogs. That’s understandable, but they know when they become taxi drivers that they have to carry guide dogs, but I can compromise by putting the dog in the boot (assuming that it’s an estate or a hatchback.
As a poster said upthread, walking into a dog friendly cafe and demanding the dog leave because of your child’s phobia is unreasonable as you knew it was a dog friendly cafe to start with.