I actually prefer to answer the 'serious' ones (not too serious like about problems o deaths etc) making them funny por saying funny non-serious stuff for an answer.... ^_^ To answer your question: cause it is easier and does not require much thought, people hate to think...
hm... maybe because when tu answer random/ funny pregunta tu don't really have to think about your answer as much tu could just say anything tu want to! ^^
Serious preguntas are very difficult to answer hence seriousness. Coming i guess people often forget the present troubles they face and such so it is easy to just answer those preguntas that does not demand much. I dont know thats just how i feel:)
Cause this is a fanclub of randomness and people who want to aks serious preguntas could maybe make another club called 'Answering the questions' o somwthing... That was just my guess,there's probably a better reason!