There is very little hierarchy. The problems of selection for promotion and jealousies are eliminated. The more everyone on the team feels they are a vital part of the operation, the better. Not everyone has to be a specialist. Each team member is responsible for and familiar with most tasks.
Any member can step in for another.
Specialization is not necessarily a benefit. Specialize when it is a benefit but not for its own sake. It should be natural to the team members. In talking to one of the waitresses, I mentioned how unusual I found their operation. She responded with an expressive look and comment indicating surprise.