That’s just the number of missing child reports. The vast majority are teens who are gone for a couple of days without telling their parents where they’re at and are found and returned quickly (92-93%).

A good portion of those reports are multiple reports for the same teenagers that repeatedly run off from home. Frequent runaway teens with 10 or more missing child reports make up 30% of all missing child reports each year. https://popcenter.asu.edu/node/37501

From a few comment below: https://globalmissingkids.org/awareness/missing-children-statistics/

And yeah, children go missing very easily. These are the number of reports. Most children are found very quickly after reporting.