A good waiter certainly has great "menu knowledge", however this is actually a situation where the waiter shouldn't be trying to impress the customer with how w

A good waiter certainly has great "menu knowledge", however this is actually a situation where the waiter shouldn't be trying to impress the customer with how well they remember ingredients. A customer informing a waiter of a food allergy should trigger a clear protocol (that the restaurant may have established in writing), which will involve talking to the kitchen/chef/manager. Many places will have waiters follow up the "does X have {{ allergen }} in it?" with clarifying questions as to whether the customer has an allergy or if it's a preference. If they are indeed asking because they have an allergy, it's critical that everyone dealing with that customer's food knows in advance so they can double check all ingredients and prep/handle the food in a way that limits any potential cross contamination.