how does the waiters figure the people on DDP and the ones paying cash? I have 11 people 9 are on DDP and 2 are not. I have a teenager that will live on mac and cheese 99% of the time, So when we order can we OP for his mac and Cheese and use his credit towards the 10th persons meal. When they total up the bill will each room us two ccredits and the ones not covered just become OP. I am very confused on how this works.