they're talking about sharing tips across the entire wait staff, which avoids fights over hoo has to take the no and low tipping Canadians' table and hoo gets the one that looks like they'll be ordering high dollar bottles of wine on the expense account. And the wait staff doesn't hesitate to also help each other running food, refilling drinks, etc. for a fellow waiter that may be slammed. Because it all leads to higher tips from that table, and thus to the team. It also leads to servers pressuring other servers to up their game on improving their service, upselling, selling desserts, etc. if any members are "slack", because it all leads to better tips for everyone.

And yes, even when it comes to tip sharing with the bussers and kitchen staff, it leads to better service. The place I was at was only waitresses, but if you were bussing, washing dishes, or in the kitchen, you, and everyone around you pressured you, knew the better you did, the better your share would be. Even when washing dishes, I knew tips went down if silverware/plates went out spotted, or food was delayed because it was waiting on me to wash the dishes needed.