Large, rich library here - and noticeably fewer books. Some categories still well stocked, like surprisingly the teens section! How does that happen? Teens are

Large, rich library here - and noticeably fewer books. Some categories still well stocked, like surprisingly the teens section! How does that happen? Teens are reading paper more than the general audience? One thing is that like you say, (some) teens are present - while the general audience may have fewer reasons to show up.