There is a non-zero chance that TV timeslots are seen by people not in the targeted group. A billboard in a school zone may have a high chance of being seen by naive young moms but the canny young moms will also see it, along with dads and grandparents picking up kids, not to mention hundreds of other people who live and work in the area.
> it doesn't make sense to make a company waste money
except it does, to keep them accountable