Where I live, there are no school zones, but instead playground zones that are in effect from 7:30am to 9:00pm. Now, I might go 60 km/h in a 50 zone depending on the road, but I will always go exactly the limit in playground zones (30 km/h). The fine for speeding in those is so much worse.

I would say the majority do the same, for probably the same reason.