What Shopenhauer is saying is that information and the storage of it in one's brain is not the goal of the lecture per-se. It is only useful as a medium to convey something more meaningful. It is useful in clearing up one's thoughts about the world, changing attitudes, raising up questions. Once you have a new question bugging your mind, it does not really matter who or what started the avalanche but only that it's rolling.

You can look at it from the point of view of modern sports. For me, at least, sport would mean having a good time, making new friends or spending time with old ones, forgetting about one's troubles, smiling and being happy about life. But sport as we know it today seems to have devolved into keeping scores and celebrating winners. That, to my mind, is akin to a information gathering activity without understanding what the purpose of it actually is.