Sometimes it has nothing to do with the economy. You can have parents who just don't want to bother with or who don't have the time (think single working parent, although I'm speaking from a U.S., no-social-net perspective) to pack a lunch and instead rely on the schools to provide food. (There are also parents who are just plain neglectful, so good for you for ensuring every kid's got the opportunity for at least one good meal.)