I really dislike olives. If I order something that normally comes with olives, I make it very clear that I would like it to come with no olives. If it comes out with olives, I will send it back because even if I pick them out, I can still taste them and I really don't like olives.
As a server, if someone orders their food without something that is normally included, it is my job to make sure the food comes out as ordered. If it doesn't, it is my job to fix it. No problem. But it bothers me when people assume I'm a fool.
The other day I had a customer order a kids caramel milk shake on soy.
"Do you still want me to put ice cream in that?" I asked the customer.
"Oh yes, it's only the milk she's allergic to" The lady replied.
Now, I don't know what allergy this child had where ice cream was ok but milk was not. I'm happy to make a soy milkshake. It's no more difficult than making an ordinary milkshake. But your child is NOT allergic to milk if she can still eat ice cream.
There are people out there who have genuine allergies that can be life threatening and there are those who are intolerant to certain foods and these will cause them varying levels of discomfort. And then there are those who just dislike something or would prefer an alternative. I don't care which category you fall into, it's my job to bring you the food or drink the way you want it if it is in my power to do so. But please, give me the courtesy of assuming I'm intelligent enough to do my job without you having to outright lie to me.