IMO, clients that I connect with the easiest/quickest (and vv) are the ones who are like me; free spirited, looking for a fun experience and don't need to spell out the why's to have fun. Sure, the monetary compensation for my time is also a nice thing, but it seems to work itself out once a connection/plans are made. So I guess, if a client is asking why, it's because they may not know enough about you and your personality. But those newer clients who may ask questions, I personally wouldn't dismiss them.
Inversely, if there are questions revolving around my personal life that I don't openly make available and these questions are asked repeatedly, I'll let the client know that I don't share those things.