There is enough context to understand the practice (other articles were all over the place: PT, a chiropracter, primary care, etc.). They did lots of research to analyze the no-show prone cohort. They didn't just fine/warn them. They TALKED to them. They did a really creative pseudo-overbooking strategy AFTER explaining it. And they mostly focused on scheduling appointments in the next few days and wouldn't allow advanced booking unless people had shown they could show up for an appointment booked well in advance.
All in all, admirable and sensible.