I had a friend e-mail me the other day asking for help with her cafe on cafe world.
She knew that I had been playing the game for a few months now and was doing way better than she was. I've got a ton of cafe coins and my buzz points are sitting at around about 105.
Her problem was that the waiters were not serving every table in her cafe, and as a result customers were leaving without sitting down.
The answer to this problem is quite simple, all you have to do is make sure that there is adequate space around all tables for the waiters to move. If a table is blocked then the waiter cannot serve the food.
