If you ask every guest about food sensitivities then you will have a miserable time innkeeping. Everyone has something that gives them a headache or indigestion...
We had guests this weekend who could not eat this nor that and I kindly requested whatever they cannot eat to please just leave on their plate (unless of course they would die by having it touch their other food). They did just that - left it on their plates - and it worked grand. To them, in their minds they want to make it easier on us to just tell us the list of things they cannot eat. They don;t realize the difficulties it causes.
I, myself will end up in hospital if I eat bell pepper. I am served bell pepper all the time, every salad or pasta or sauce has them thrown in for color - even if I order a pizza one might land on the pizza. I have to be super careful and when they appear to be in something, so I just don't eat it. I tell folks if we are invited for dinner I cannot eat it and there it is.
Case in point this homemade chili set up - please please I am not being difficult, really. She told me it was homemade, yes I believe it was she browned the meat, added the beans and cans of tomatoes and then used a packet seasoning mix. I can guarantee she did. I asked and embarrassed her - it was either that or not eat the entire meal. She told me out right they would never put bell pepper in chili seasoning (me - they could never NOT put it in chili seasoning -ask Wendy's it is in there). She retireves it from the bin outside the house and then is shocked to read it in the ingredients. She said "I didn't know" the salsa she had out also had bell peppers in it. PACE picante has no bell peppers fyi in case you hate them or allergic. Marinara sauce typically has them in it. American mexican restaurants have them in everything, Mexican mexican restuarants don't use bell peppers. Chile peppers yes, not bell peppers.
It is not fun. It is a terrible allergy to have. My partner is allergic to shellfish, that is not as easy to sneak in, but we still have to convince people that fake KRAB dip has real crab meat and juice in it, like 15%.