Well the idea of audios isnt really to be amusing it's to help you learn, but true, I admit, humerous audios are enjoyable, but not everyone has a talent at being funny plus I reckon some people wouldnt dare try and be funny cos people would just call them "lame".
Why not make a comical member audio if you like your humour, why not share it with everyone else? (Thats not meant to be harsh or anything btw, just saying, why not? :P)
yes, comical audios are entertaining, but so are educational ones, and that is the primary purpose of AC's.