This happened in 2017 on American Airlines. I told the flight attendant when I boarded that I had a severe seafood allergy but that it shouldn’t be a problem, unless someone brings seafood on board. She gave me a funny look, but that’s usually the reaction I get, so I was not alarmed.
About halfway into the flight, I got up to go to the restroom. As my hand was on the handle to the door, the flight attendant tells me “don’t go in there, there are shrimp.” I stop and must have looked like a deer in headlights. She giggles with the other flight attendant. I realize she is joking but still cautiously open the door, because she just triggered my anxiety.
When I left the restroom, the attendants were still all laughing. There was absolutely no reason to make that comment. They went out of their way to do this to me. Food allergies are not funny, would she dare make fun of someone with a visible disability? I was anxious the rest of the trip, if she thought making that joke was funny, would she do something else to get a laugh?