I think this is a horribly bad idea. Daycare caretakers are the most loving and caring people I know. Putting them in a position where they have to argue with 3x richer people about hundreds of dollars is going to stress them out and needlessly strain the parent-caretaker relationship. I also can't imagine that's good for the child.

That may be. In this case, the daycare is just an example of how inflexible financial consequences could work better or worse depending on the implementation.

That said, if lateness is a problem, it’s impeding on the workers’ personal lives, which can’t be good for anybody, so I don’t mind exploring how those workers could be helped. I assume more upfrontness from the business office, and parent education, would go a long way, similar to other institutions.

This problem can be solved by hiring a professional who doesn't interact with the children to do the arguing, assuming there is enough money on the table to make that worthwhile.

(I mean, I agree it's a big problem. I also dislike haggling, and I think I would have done much better had i outsourced that function when I ran a business, even if I paid a lot to that person)

All that said, a sufficient guilt trip might be more effective than a fine in any case, and is something that a caretaker could probably provide.