The owner could never keep track of who had classes or specific commitments, so they would get together (originally in person) to independently swap shifts and make sure the people who needed more hours could get it. A few hours of communication, the schedule would be completely revised.

This was the peak of app-dreaming, and I always figured it was a matter of time before a ubiquitous shift scheduler took over the industry. The crucial piece would be giving workers a level of autonomy that would be challenging for management to accept. As far as I can tell, no app ever took off, but this flexible work option sounds like an evolution of that idea for a much larger operation.