Critique and Advice; the treadmill of adventuring.

Even then what should be avoided is the author using a character as a soapbox for their ideas - that gets old real quick.

I don't exactly remember how the phrase goes, but it's something like "All cartoons are political and all writing is didactic." I think the problem isn't spreading ideas, but bad writing.

You know the story of the Dude of Wisdom humiliating a Loud and Irrational Straw Guy for not being like the Dude of Wisdom? It's a classic, almost as old as the Hero's Journey. It's also bad writing because it's just as entertaining no matter what the Dude of Wisdom's viewpoint is.