Having seen this article in the Milwaukee Business Journal, however, I now know that it will also let everyone who needs to know that I'm "in the house."
Built into a Bonefish Grill food register is a button that reads “food
allergies” that alerts the kitchen staff that they’re preparing a meal for a patron with dietary restrictions. All dishes are made from scratch, allowing chefs to eliminate or substitute individual ingredients. Kitchen and wait staff receive in-house training on food allergies.