I like onions just fine, and cook with them all the time. But honestly, if someone told me they just couldn't stand them or they made their stomach hurt - I'd leave them out! I absolutely hate the notion that people make up an "allergy" because they don't like something. I guess there's a reason we have difficulty with people thinking allergies are just "in people's heads"!
Sorry, I know I'm a bit off topic - but that just really bothers me!