Peanut is different. Allium family allergies are less common, and less likely to be severe. Peanut is also very persistent in a catering environment so it's easy to contaminate things invisibly. Everybody can do without peanut, or bring their own, for a few days. It doesn't have to be compulsory.

Bags of roasted peanuts are a menace on a plane because it's a closed environment and because of the way they're distributed, you might get 200 packets opened at once with their fine particles being spread through the air. You don't want to replicate a situation like that. With fish/shellfish allergies, the most serious threats are also respiratory, with food particles being released in cooking. This is manageable if any such cooking operations happen in a small predictable area.

I get violent sneezing fits from lemon-scented cleaning agents (when I was in hospital after my heart attack I got the ward to stop using them, as one of those fits could have killed me). Allergy to pine-scented household cleaning materials is more common than my sort (usual reaction is allergic asthma). Unscented cleaning products are available; use them.