Principally because they help you do the set up and help you deal with proper tea service. It's served at fine hotels. I also recommend Cafe La Semeuse. I've had elsewhere. It is served at Lutece and Silver Palate.
Service is the key.
Serve only sandwiches and salads at the stations and make sure that you have heavy base glasses or cups for the stations. Don't go fancy with the china and glasses for this area. Also, keep several keyboards and mice handy to make prompt replacements. I only had one keyboard problem with a spilled beverage in a year. Thank you very much for your time, Robert.