Sure, if you add presymptomatic and asymptomatic spread you get a large number (because the most infectious period is the presymptomatic period right before symptoms develop.) That doesn't even begin to contradict asymptomatic spread, distinguished from presymptomatic spread, being rare to nonexistent. Usually, this makes little difference because you can individually distinguish the two only in retrospect, but when you have a population (like children) that demonstrably has a much lower propensity to develop disease symptoms when infected and a much higher propensity to remain asymptomatic, it makes a big difference.