There are two reasons that restaurateur’s are afraid to engage the customer. One, there is a concern that they might alienate the customer with the interruption. Two, there is this perception that the restaurateur needs to respond right then and there to the guest's answer.
Creating customer advocacy is all about engaging the customer so get over it.
Two, Blanchard’s view is that you owe the customer your undivided attention in listening to their answer, however you do not need to respond right then and there. That is a very liberating because restaurateur’s have this notion that they need to respond immediately to customer queries. Certainly the customer needs a response, however the response can be, “that is very interesting, Thank you I will consider the view you have graciously expressed to me today.” The response acknowledges the input of the guest, while allowing other variables to be factored into the decision.
Listen, then Respond!