In a customer service setting, often times that's all you can do. The customer knows what they want, and particularly if there's money to be made, your employer will require you to do so. It sounds like this place wasn't exactly like that, but dude said multiple times this was unnecessary, and the customer still wanted it. He told them it'd be long and expensive. And unnecessary. They said do it. At a certain point, we have to trust that the customer really is their best advocate, and just do what they want.