If you're a kid who's not necessarily attractive and you don't have money and you're not hip and cool chances are you're not going to feel good about yourself and want to be an actor.
I do think sometimes there's danger in guest appearance mania. I've seen too many examples that sound cool on paper like 'Oh get that guy to sing the hook on that guy's song ' and then that's all it is. It's a cool idea that sounds good on paper.
