In the UK business owners have been arrested for accidents caused by non displayed allergens. It caused death.
Well... indipendent take away owners got arrested. Pret a manger got a warning when a young girl got killed on a plane by non displayed sesami seeds I side the baguette. And another chain got another warning when a teenager got killed by the dairy in the bread of a cheeseburger.
I have a business in the food industry and I dealt with allergy info and staff training for many years.
I have to admit is a lot more difficult now.
First, if you are at risk of life, you can NOT trust ANY food preparation areas. Nowhere is safe if the ingredients that can kill you are in the room. Shit happens and anything can fly over or inside somewhere where it shouldn't be. If your server is well trained, they will probably admit to that, when the customer is at high risk and ask for what's safe. Nothing prepared in a cafe or restaurant is safe if you are at risk of anaphylactic shock, I am sorry.
Then you have... Intollerances, trendy fashion crap, dietary and ideological reasons.
With all respect to any need, the huge demand cause a confusion. At the end of the day... Your servers are not doctors.
You have a huge demand for alternative milk, unbelievable demand compared to a few years ago.
People go in shop and restaurant and claim to have mom scientific issues, just to make a point and try to get the best attention. They have a mild intollerance, or just believe a YouTube video saying that gluten is bad for you, and they all it an allergy.
Ignorant servers get confused and tend to diminish the problem, when everyone has one.
So you get lots ignorants dealing with other ignorants... And the high risk individual pay the price.
Used to be different a few years ago. Cases where rare and your server used to inform the chef, manager or supervisors when that's the case.
20 years ago all restaurant would know that there is a nut allergic having dinner.
Today, every table claim an issue or a dietary need.
Vegans asking if their food is grilled in the same grill or if touches the same chopping board are extreme on a religious level.
I love vegan concept and understand lots of need. But even as business owner I believe some people with need should learn how to cook and eat at home. And if you kids have serious allergies, send them off with packed lunches instead of letting them buy take away for themselves.