YCombinator's application is not hoop-jumping. It's training. These are questions that you should be asking yourself about your idea anyway, regardless of whether you seek YC funding. Big-time VC funds will ask you the same questions, except that they require a personal introduction to even get to that point. Heck, customers will ask you the same thing, except that they want you to show them the answers through your product instead of tell them through an application form.
Also, the value of YCombinator is not in the $20K. It's in the introductions they give you, and how hard they work to put you in front of big-money investors. We saw that a couple days ago with the e-mail exchange where PG tried to get Union Square Ventures to invest in AirBnB. Most investors won't even look at you without a personal introduction from someone they trust.
Yes, VC's ask a lot of questions. Even harder ones. They even want very long business plans. And more. The difference is VC's are going to give you MILLIONS of dollars if you jump through all their hoops. Not just a little more than what would pay your relocation and rent while you move to California. I trust you can see the difference.
Also, are you sure you read/reread my post? I clearly said in there "Yes the intros are a good perk, but if you truly have something, you will get there regardless." So I'm wondering why you bring up the intros as a perk beyond the money as I already pointed that out in my post.