Kind of like introducing a defect lane on your factory line makes the workers feel like it's OK to have defects, and deters from quality.
The economic premise of the kindergarten is already that parents would rather pay money than spend time with their kids.
http://freakonomics.com/2013/10/23/what-makes-people-do-what...
Social mores are actually huge efficiency boosters for humans. They remove the overhead associated with coordination, transactions and ensuring trust.
I understand that a lot of these don't scale to cities of millions and civilizations of billions, but some do, and we shouldn't be quick to replace them with the "newest and shiniest" (essentially replicating them at scale by burning energy).
Some human interactions are only a few A/B tests away from turning into a Black Mirror episode.
In the case of the daycare, the price wasn't intended to encourage parents being late at all. The actual price the daycare workers would probably want to charge is not a market clearing price, but a price so high the market doesn't clear. They probably felt trapped into haggling once they put any price on the practice at all.
"Staying open later and charging your customers for the service they receive during that time" isn't exactly a business secret. It also can be detrimental to the quality of life of the employees that are unsure of when exactly they'll be able to end their shifts.
Set it to something really high like $600 [0] and parents' behavior will change, problem solved :)