Nuts seem to invoke severe reactions in some people, both medical and opinion. If someone just comes out with a rash if they eat them the fuss seem's a bit much - but others can have a far more severe reaction, and taking measures is called for...
I say this after Nutgate last year. A row between PTA mothers as to whether Peanut flavoured Cornetto's could be sold at a school event, as one boy had a nut allergy of the minor kind..