I would say that it probably more of an incentive for them to control the kids. You have to remember that whole idea of discipline has gone out the window in most schools. Today instead of keeping a kid after school they send him or her to the school psychologist.
Certainly agree with that.
But..
I have a teacher friend that told me the schools get paid according to their attendance each day. If the attendance falls below a certain percentage they lose money. IIRC 90%.
The school actually goes out on the street and pulls people in to make the quota on lean days. Strangers!!