I like to leave a hand-written note for my guests upon arrival (it's a self-contained suite with separate entrance), and have found these questions to be useful in personalizing the notes, as I ask what brings them to town. Sometimes guests will answer, which helps me to plan for their stay. I had guests once who were moving to town for new jobs and they were a few days between homes. I gave them a bottle of champers (ok, sparkling wine...I'm not that much of a spendthrift) and a "welcome to the newest steps on your journey" note. It's a pleasure and a privilege to be a small part of guest's life changes.
Often, though, people don't bother to answer the questions. I do find it a bit awkward to include the questions in my "thanks for booking" message, as it seems somehow a bit more intrusive to ask after they've booked. This is my own issue, likely, and I'll just need to wrap my head around wording a new "thank you" message.
I have yet to receive the email everyone is discussing though. I guess it's just a matter of time. You'd think that an automated message like that would be rolled out simultaneously - at least to hosts in the same region. Odd.